Forum:Reasons why cards are Forbidden/Limited

List

Due to an issue with displaying the list from another page, I have moved the list to the main page, and all discussion will now have to take place in the current discussion page (see below). Thank you for your understanding. --VictoryViperXX03

• From the creator of the "List of cards to side in to cripple meta decks", comes the...

List of Reasons for Why Cards are Forbidden/Limited
Card Name	Reasons
Forbidden
Amazoness Archer	Cannon Soldier and its ilk are classic burn FTK enablers with no once-per-turn restriction which can be used in many strategies. The original was infamous, but spared being Forbidden for so long (unlike its faster Spell counterpart, Mass Driver) since it has the disadvantage of requiring a Normal Summon or another card to Special Summon it. The game is much faster now, and methods to Special Summon it and its counterparts easily are widespread. In particular, various Link-era burn strategies featuring Firewall Dragon (now Forbidden) and the player's choice of engine brought them to the fore enough for them to be Forbidden. Amazoness Archer and Toon Cannon Soldier are technically greater threats than the other two, due to them being searchable. These cards are Unlimited in the TCG.
Cannon Soldier
Cannon Soldier MK-2
Toon Cannon Soldier
Ancient Fairy Dragon	Can be Summoned very quickly by Destrudo the Lost Dragon's Frisson, which then allows you to remove a Field Spell, heal, search another Field Spell, and get a free Special Summon all in one turn. This is highly abusable in Decks whose Field Spells have on-activation effects or non-HOPT effects, like Union Hangar and SPYRAL Resort. Can be looped with Recycle to pull off its Field Spell effect each turn, with a net gain of LP too.
Astrograph Sorcerer	Key card in Pendulum Magicians that generates ludicrous advantage. When a card you control is destroyed, it can Special Summon itself from the hand and add a copy of the destroyed card from the Deck to the hand. Can be triggered and looped fairly easily with Heavymetalfoes Electrumite. Being Level 7, it can be used to access Odd-Eyes Absolute Dragon, which provides more advantage, and brings out Odd-Eyes Vortex Dragon, with its removal and negate effects, when it is sent to the Graveyard by any means. This card is Limited in the OCG.
Blackwing - Gofu the Vague Shadow	Level 5 Tuner with a Cyber Dragon-like effect. Special Summons two Tokens when it is Summoned by its own condition, allowing you to revive a Blackwing Synchro Monster from your Graveyard. Allows for easy plays into Ultimaya Tzolkin, which easily Summons high-Level Dragon Synchro Monsters such as Beelze of the Diabolic Dragons or Crystal Wing Synchro Dragon. The Tokens it Summons allow for fast Link Monster plays, and make it a "1-card Link-3".
Blackwing - Steam the Cloak	Summons a Token when it leaves the field, and can be revived quickly after that for one Tribute, which gives an easy Synchro or Link Material. One of the cards of choice to Summon Crystron Needlefiber, which generates easy card advantage and can bring out a Synchro Tuner on top of that. This card is Unlimited in the TCG.
Blaster, Dragon Ruler of Infernos	Incredibly powerful Dragon monsters. Can be Special Summoned easily from the hand or Graveyard by banishing any 2 Dragon monsters and/or monsters of their same Attributes from the hand or Graveyard. Can be put into just about any Dragon Deck, or Deck of their own Attributes, to add huge power and consistency. At more than 1, they can search another copy of themselves when they're banished to Summon another Dragon Ruler, or when banished with Sacred Sword of Seven Stars or Gold Sarcophagus. Can be used in OTKs with Number 95: Galaxy-Eyes Dark Matter Dragon (also Forbidden), as one can simply dump 3 Rulers into the Graveyard when Summoning it, allowing the Rulers to be revived or to search other Dragon monsters. Tempest is Limited in the OCG.
Redox, Dragon Ruler of Boulders
Tempest, Dragon Ruler of Storms
Tidal, Dragon Ruler of Waterfalls
Cyber Jar	Destroys all monsters instantly. Unlike Morphing Jar #2, this has a set number of cards to get, allowing players to gain instant advantage easily. Swarms the field by itself and can create OTKs and can give either player crazy advantage. Can wipe out a whole field of boss monsters effortlessly. A bit slower and harder to use now with THRIO and Starlight Road in the game, but can still turn an entire game around in an instant.
Daigusto Emeral	First effect can revive strong beaters or combo pieces. Second effect enables easy recursion for any Deck and can generate loops if used alongside other recyclers like Pot of Dichotomy and The Transmigration Prophecy, even at 1. This card is Unlimited in the OCG.
Dandylion	Compulsory effect, triggered when it goes to the Graveyard by any means, which gives lots of advantage most of the time. Re-usable in many Decks. Produces Tokens for fast Synchro and Link Summoning.
Denglong, First of the Yang Zing	Can search ANY Yang Zing card upon its Summoning, and due to the wide variety of Levels the Yang Zing monsters share, it can function as almost any necessary Tuner, while sending Chiwen, Light of the Yang Zing to the Graveyard to easily activate its revival effect. In addition, if it leaves the field it Special Summons another "Yang Zing" from the Deck, extending the chain of defensive monsters or Synchro/Xyz/Link Materials. Also, unlike several other Yang Zing monsters' effects, neither effect can miss their timing, leaving few options open for the opponent to stop them from activating. This card is Unlimited in the OCG.
Djinn Releaser of Rituals	Prevents your opponent from Special Summoning when used for a Ritual Summon, and can be banished from the Graveyard to be used for a Ritual Summon as well. Mainly Forbidden due to abuse in the Nekroz archetype, where it was mainly used to Ritual Summon Nekroz of Clausolas, which can search Nekroz Cycle by its own effect, which can then Ritual Summon Clausolas from the Graveyard by using Djinn. Can be searched with Armageddon Knight, Lavalval Chain (Forbidden) and Tour Guide from the Underworld (Limited). This card is Unlimited in the OCG.
Double Iris Magician	Key card in Pendulum Magicians. Easily pulled from the Deck and thrown straight into the Extra Deck by Heavymetalfoes Electrumite. Searches the powerful Pendulumgraph cards when it is destroyed (e.g. by Wavering Eyes, the Electrumite that Summoned it, or another Pendulumgraph), which enables further searching. This card is Limited in the OCG.
Elder Entity Norden	Powerful and generic Fusion Monster that can revive any Level 4 or lower monster from your Graveyard for easy Rank 4 Xyz Summons or Synchro Summons with Instant Fusion, or can be used with Super Polymerization (Forbidden in the TCG) to fuse two of your opponent's Synchro or Xyz Monsters to make this card. Can be Summoned multiple times with Re-Fusion and Fusion Gate for OTKs and even FTKs. Enables draw loops when combined with Zoodiac Xyz Monsters, Fusion Substitute, Lunalight Black Sheep, and Daigusto Emeral (Forbidden in the TCG).
Fairy Tail - Snow	Sets an opponent's monster when it is Normal or Special Summoned, and can be Special Summoned during either player's turn by banishing 7 other cards from your Graveyard, field, or hand, which is abusable in Infernoid or Lightsworn Decks since they can easily get lots of cards into the Graveyard. Can even be used multiple times per turn. Combos well with That Grass Looks Greener for this very reason - banish what you don't need anymore, and use Snow as material again and again, shutting down Effect Monsters in the process. The advent of Links was mixed for Snow; Links can't be Set, but their overall generic nature made the revival effect even more potent. This card is Unlimited in the OCG.
Fiber Jar	Even though it's slower and harder to pull off than it once was, it resets almost everything. It even puts itself back into the Deck when flipped. If used in a Deck with cards like Soul Release, you can slowly banish your opponent's entire Deck, giving them a smaller one each time Fiber Jar is used.
Firewall Dragon	Powerful FTK, swarm, and Extra Link enabler, to the extent that being able to Summon it can effectively guarantee a win. Its first effect bounces both your cards and your opponent's, removing their defenses while allowing you to recycle on-Summon effects that aren't a hard once-per-turn, including Grinder Golem (Limited), or itself when used in multiples. Also allows you to recycle handtraps from the Graveyard. Allows a free Summon when a monster it points to is sent to the GY by any means, making it even more suited to Extra Link shenanigans. Is the sole reason why several cards have been on the list at all.
Fishborg Blaster	An infinitely-reusable Tuner, although restricted to being coupled with only WATER non-Tuner monsters. Can cause easy OTKs when used with cards such as Superancient Deepsea King Coelacanth. Broken with Formula Synchron and T.G. Hyper Librarian. Fishborg Launcher was designed to replace this card. With the release of Atlanteans, this card would create even more powerful combos and loops if it were to be unbanned.
Gandora-X the Dragon of Demolition	In the OCG, this card's burn effect calls for the ATK on the field instead of the original ATK when determining how much damage to inflict, so FTKs become highly viable with this card by simply increasing the ATK of your own monsters. Initially, this was done with Number 95: Galaxy-Eyes Dark Matter Dragon (also Forbidden) and the ATK-doubling card of choice, which led to 95's ban. Since then, many more ways to get a monster to 8000+ ATK were found, forcing this card's OCG ban. This card is Unlimited in the TCG (since its different text specifies original ATK instead).
Glow-Up Bulb	Easily recyclable once-per-Duel through its own effect, allowing it to work as material for 2 separate Synchro, Xyz, or Link Summons as desired. Self-mills as well as reviving. Can be used in the classic Plant Synchro engine, in Extra Link turbo, and was also used in Future Fusion OTK Decks (though that's no longer as fast due to Future Fusion's errata). No sense in just Limiting it, as no one would run more than 1 anyway. This card is Unlimited in the TCG.
Grinder Golem	A powerful asset to Link-spamming Decks, as the Tokens it Summons (not restricted to once-per-turn at all, and without any cost except your opponent having a free Main Monster Zone) can help to bring out a Link-3 or -4 extremely quickly, including Firewall Dragon (also Forbidden) and Saryuja Skull Dread with all of its effects. Its disadvantage of Summoning it to your opponent's field can be worked around either with removal or bouncing it back to the hand (for example, with the aforementioned Firewall Dragon), allowing it to be reused again. This card is Limited in the OCG.
Knightmare Goblin	Key card to a Knightmare lockdown. Generates advantage with its draw and Normal Summon. An Extra Link with this card (along with Mermaid (also Forbidden in the OCG), Cerberus, and Phoenix) locks the opponent out from using the Extra Deck at all and makes all Links involved untargetable by card effects, which can prevent the opponent from playing at all. Add Tri-Gate Wizard for additional "fun".
Knightmare Mermaid	Grants an easy Summon from the Deck, which instantly starts a Link ladder. Used heavily in Decks that use the "Orcust Combo", where this card was used to Special Summon Orcust Knightmare and climb into Galatea, the Orcust Automaton, ending in a board of 4 disruptions from a 2-card combo, and easy access to Orcust Crescendo for further negation. This card is Unlimited in the TCG.
Lavalval Chain	Can easily be Xyz Summoned in Rank 4 Xyz Decks, and sends any card from your Deck to the Graveyard or stacks any monster in your Deck on the top. Mainly hit for causing loops and OTKs due to its lack of an once-per-turn restriction between multiple Lavalval Chains, or possibly to pre-emptively hit the Clownblade Deck that was topping in the OCG.
Level Eater	A searchable Level 1 monster that can revive itself any number of times per turn so long as you have a Level 5 or higher monster on your field. While it was always a popular Tool in Synchro Decks, it was barely relevant until DARK Synchro Decks with more Tuner Synchro Monsters abused this card for combos that can banish the opponent's entire hand in one turn with PSY-Framelord Omega (Limited in the OCG) or Trishula, Dragon of the Ice Barrier, Summon two Shooting Quasar Dragons in one turn, as well as acting like near-infinite revival fodder. Can be used in Knightmare Decks to lock down the opponent very early on.
M-X-Saber Invoker	Generic Xyz Materials, and brings out more quick and easy materials with its effect. Summoning it is made much easier with cards such as Speedroid Terrortop (Limited in the TCG), Psychic Wheeleder/Tracker, Marauding Captain... Abused in both Zoodiac and Gouki/Knightmare Decks, as their monsters are EARTH Beast-Warriors or Warriors, to generate Xyz or Link Material.
Magical Scientist	Pulls a Fusion Monster directly from the Extra Deck for only 1000 LP. Was initially hit due to its role in the Catapult Turtle FTK, but Turtle's errata patched that out. Can also be used to quickly Summon multiple Link and Xyz Monsters by using the monsters it Summons as material, though this is ultimately slower due to New Master Rule. LP cost can be circumvented with DNA Surgery (calling Psychic) combined with Brain Research Lab or Telekinetic Charging Cell, removing whatever limitation the card had and resulting in virtually unbreakable fields filled with Extra Deck powerhouses. Can be searched by Where Arf Thou? and some of the Prophecy/Spellbook cards.
Majespecter Unicorn - Kirin	Splashable Pendulum Monster with a good effect. Can return one card from both player's fields back to the hand during either player's turn, allowing you to reuse certain cards again on your turn, or disrupt important plays during your opponent's. Is also immune to being targeted or destroyed by the opponent's card effects, making it hard to remove outside of battle. With the release of Link Monsters and New Master Rule making this card even stronger than before, its very unlikely to ever come off the list now.
Makyura the Destructor	When sent to the Graveyard from anywhere, by any means, this card allows for Traps to be activated from the hand for the rest of the turn. A lot of Trap Cards have powerful effects that are balanced due to the fact of them needing a turn to be activated; this card removes the downside. Being an effect that doesn't activate, it bypasses a lot of negation options. Sets up OTKs and FTKs which would be impossible otherwise, such as the Dark Scorpion/Makyura OTK.
Master Peace, the True Dracoslaying King	Powerful boss monster that can easily be Tribute Summoned by Tributing Continuous Spell/Trap Cards as well as monsters, and is unaffected by effects of cards that have the same card type as the cards Tributed for its Summon. This often results in it being vulnerable to just 1 in particular, which you may not have easy access to at that point in the Duel. Can also destroy any other card on the field during either player's turn by banishing a Continuous Spell/Trap from your Graveyard, disrupting plays during your opponent's turn and clearing the way for OTKs.
Maxx "C"	Very effective handtrap at countering Decks that Special Summon constantly, allowing you to draw 1 card every time they do. When chained to an opponent's effect that can/will Special Summon, you'll lose no hand advantage. You'll gain further pluses if they decide to swarm anyway, or prematurely end their turn, leaving themselves open to a retaliatory OTK. Can also be searched by Retaliating "C", another handtrap. This card is Unlimited in the OCG.
Mind Master	Very similar to Substitoad (who is also Forbidden), except you pay 800 LP each time (or you can use 1 more card to bypass it). Creates many OTKs/FTKs, including an attacking OTK with Reinforced Human Psychic Borg and many draw-out FTKs with Caam, Serenity of Gusto. Can be searched by Emergency Teleport and One for One.
Morphing Jar #2	A very potent field-disruptor, freezing the Battle Phase and eating up Nomis, Tribute Summoned monsters, and Extra Deck monsters the moment it is flipped while resetting the field. Can create outrageous OTKs/FTKs, especially with All-Out Attacks or Jackpot 7. This card is Unlimited in the OCG.
Number 16: Shock Master	Creates an immediate lock/OTK and can ruin an entire Deck, depending on what type of card they use most. Easily Summoned in the first turn in most Rank 4 Xyz Decks. Can outright win games if played alongside other lockdown cards.
Number 42: Galaxy Tomahawk	Special Summons Tokens en masse to the field, essentially allowing for a free Link-4 or multiple smaller Links. Allows the player to set up Extra Links and lockdown fields. Rank 7 is not a difficult Rank to make, so it is Summoned easily. This card is Unlimited in the OCG.
Number 86: Heroic Champion - Rhongomyniad	Powerful lockdown card with several possible Turn 1 combos to Summon it (via Isolde, Two Tales of the Noble Knights, and hence, various Warrior engines such as Goukis) that require very little hand luck. The major threat is its combo with Number 75: Bamboozling Gossip Shadow, which can attach itself and all of its materials to Rhongo with its own effect. With 5 materials, it acts as a field nuke that locks your opponent out of Summoning for 2 whole turns, which is devastating in the current game, and as such, the "Rhongo Bongo" Deck, which focuses on turboing this out, came into power. This card is Unlimited in the OCG.
Number 95: Galaxy-Eyes Dark Matter Dragon	When it is Xyz Summoned, it dumps whatever Dragon monsters you want in the Graveyard and forces your opponent to banish 3 monsters from their Deck. Fairly easy to bring out despite being the awkward Rank 9, as it can be overlaid on any Rank 8 Galaxy-Eyes. Can cause OTKs with Dragon Rulers. Can set up a lockdown by dumping Amorphage Goliath and Arkbrave Dragon. Banned for its role in an FTK involving Gandora-X the Dragon of Demolition; this was thought of as OCG-only (since Gandora-X's damage depends on current ATK in that format), but an alternate combo was found that involved halving the opponent's LP first, and then Gandora-X would destroy this card. This resulted in its TCG ban.
Performage Plushfire	Too abusable. Spawns any Performage monster from your hand or Deck whenever it is destroyed without any restriction, and is easily recyclable by being a Pendulum Monster. Combos well with Wavering Eyes, Performapal Pendulum Sorcerer, and Luster Pendulum, the Dracoslayer (Limited in the OCG).
Performapal Monkeyboard	Key card in Performapal Decks. Can search any Level 4 or lower Performapal Monster when it is activated in the Pendulum Zone, allowing you to set up both Scales by itself to Pendulum Summon practically for free. Can be searched easily itself by Performapal Skullcrobat Joker, Performapal Pendulum Sorcerer, and Wavering Eyes.
Performapal Skullcrobat Joker	A Stratos for Performapals/Magicians. It can single-handedly set up a Pendulum Summon by searching Performapal Monkeyboard (also Forbidden), and can search Performapal Pendulum Sorcerer to further thin the Deck and set plays up. Also searches Double Iris Magician (also Forbidden in the TCG). The list of combos this card enables means the fact that it requires a Normal Summon ultimately doesn't matter. This card is Limited in the OCG.
Phoenixian Cluster Amaryllis	Part of an FTK loop involving Topologic Bomber Dragon where, if you could dump enough Plants into the Graveyard (using cards such as Lonefire Blossom and Predaplant Ophrys Scorpio, both Limited in the OCG), you could revive and destroy it again and again to inflict massive damage to your opponent.
Red-Eyes Darkness Metal Dragon	Absurdly easy to Summon, with high ATK, and costless +1. Splashable in any Dragon Deck. Particularly problematic when used with Inferno Reckless Summon in Hieratics (which will Summon it with 0 ATK and make it IRS-legal.) Needed to be hit because most Dragon Decks were topping. Can be searched easily with Eclipse Wyvern. Being easily Summoned and Level 10, it makes it easy to Xyz Summon high Rank monsters such as Number 81: Superdreadnought Rail Cannon Super Dora and the other Rank 10 Trains. Finally Forbidden in the OCG after abuse in Guardragons, which pretty much sealed its fate. This card is Limited in the TCG.
Samsara Lotus	No once-per-turn restriction on its Summon. Used in another Topologic Bomber Dragon FTK, where Trickstar Black Catbat (which inflicts 200 damage to the opponent each time a monster it point to is destroyed) would be co-linked with Knightmare Cerberus would be co-lnked (making both immune to Topologic), and Lotus revived the other zone pointed by Black Catbat and destroyed repeatedly, burning the other player to death. This card is Unlimited in the OCG.
Substitoad	Poorly-designed card, able to mill most of your Deck in one turn. No once-per-turn restriction. Combos well with Pot of Avarice (which is also Forbidden in the TCG). See also: Frog Burn FTK (The most consistent burn OTK/FTK Deck for the March 2010 format). Tradetoad was designed to be a fair version of it.
Summon Sorceress	Extremely powerful. Allows the searching of cards that can't normally be searched, and can set-up mass Link Summons with a view to an Extra Link, especially in conjuction with Firewall Dragon and/or Crystron Needlefiber. Also sets up various FTKs by pulling out just the card you need (usually one of the Cannon Soldier-type burn cards) straight from the Deck. Your opponent gaining a card doesn't matter, as they'll never get to use it. Highly abusable in ABCs.
Supreme King Dragon Starving Venom	Easily Summonable by Contact Fusion in Pendulum Decks. Its effect to gain the effects of a monster in the Graveyard allows it to mimic Lyrilusc - Independent Nightingale, which until the End Phase makes it gain 4000 ATK (for a total of 6800), become unaffected by any other card effect, and enables it to inflict 4000 damage to your opponent once per turn. This guarantees an OTK if you can bring out 2, which is trivial in Pendulum Magician builds. This card is Unlimited in the OCG.
Tellarknight Ptolemaeus	Generic Rank 4 Xyz Monster that can be made with up to 5 Level 4 monsters, and can Summon a Rank 5 Xyz Monster from your Extra Deck by detaching 3 materials and using itself as Xyz Material (and is chainable). Mainly Forbidden for being able to Summon strong monsters that shouldn't normally be possible for most Decks, such as Constellar Pleiades, Cyber Dragon Nova (which is then used to Summon Cyber Dragon Infinity), and Outer Entity Azathot. Tellarknight Vatlamyus was designed to replace this card.
The Tyrant Neptune	High-Level monster with an effect similar to Phantom of Chaos (now Unlimited; see below). Was Forbidden because of an OTK with "Lyrilusc - Independent Nightingale" (which is easily Summoned by "Instant Fusion"), where this card copies Nightingale's effect, which gives it 6000 ATK (5000 with its effect + 1000 from "Nightingale" itself), makes it unaffected by any other card effect, and enables it to inflict 5000 damage to your opponent once per turn, guaranteeing an OTK if it survives your opponent's turn. Differently from most other effect-copying monsters, Neptune does so permanently, making it particularly difficult to remove due to said immuniy. Nothing that Crystal Wing Synchro Dragon or Kaijus can't handle, but it's still terrifying to go up against otherwise. Can also be searched by King of the Feral Imps.
Topologic Gumblar Dragon	Powerful, generic hand-destroying colossus. While in the Extra Monster Zone, punishes your opponent for Special Summoning. Extra Linking with this card is not hard, considering the existence of various cards like Knightmares, and this unlocks an effect which allows for costless hand destruction and devastating burn, effectively allowing you to stun your opponent and burn them to death. This card is Unlimited in the OCG.
Tribe-Infecting Virus	Either a Lightning Vortex on legs or a Snipe Hunter on steroids. Most powerful against Decks that consist of a single Type. No once-per-turn restriction allows the possibility to clear the entire field for trivial effort. Tribe-Shocking Virus was designed to be a more balanced version. Can be searched easily with Summoner Monk. Capable of powerful combos in Atlanteans. This card is Unlimited in the OCG.
True King Lithosagym, the Disaster	Can generate excellent advantage due to its interactions with other cards. By destroying cards like "Babycerasaurus", "Baobaboon", "Petiteranodon", and other "True Kings", the cost of Summoning this card is effectively nullified. True King of All Calamities can even go a step further by making that cost an efficient nuking tactic in an open game state. Additionally, it can banish three cards from the opponent's Extra Deck of your choice, which is not only rare among others like it, but devastating for Link Summoning Decks. It also revives a non-EARTH Wyrm when destroyed by a card effect, which is easy to trigger. This card is Unlimited in the OCG.
Victory Dragon	Was Forbidden on principle due to being able to interact with something outside the current Duel. Since victory conditions don't count as effects, cards like Skill Drain and Forbidden Chalice are useless against it. In tournaments, an opponent could surrender or intentionally try to receive a Game Loss penalty in an attempt to lose only the Duel instead of lose the entire Match with this card's effect. Led to judge declarations involving "unsportsmanlike conduct" and major ruling hassles during the time it was playable.
Wind-Up Carrier Zenmaity	Very easy to Summon in Wind-Up Decks. Starts up and creates nasty loops such as the infamous Wind-Up Hand Loop. Takes any 2 Level 3 monsters to Summon, rather than being archetype-specific. Summoning it pretty much meant you would swarm. This card is Unlimited in the OCG because Wind-Up Hunter (below) is Forbidden there.
Wind-Up Hunter	Key card of the infamous Wind-Up Hand Loop along with Wind-Up Rat and Wind-Up Carrier Zenmaity (which is Forbidden in the TCG). Can be searched by Fire Formation - Tenki and most of the Wind-Up cards. This card is Unlimited in the TCG.
Yata-Garasu	One of the very first cards to be put on the banlist. Easily prevents a player who is behind on resources from ever recovering. Under very specific circumstances, it can even prevent a player from making a move for the rest of the Duel (see Yata-Garasu Lockdown). Can be searched easily by Aratama and Tour Bus To Forbidden Realms.
Zoodiac Broadbull	Generic 2-material Rank 4 Xyz Monster that can also easily be Summoned by using any other Zoodiac monster you control as material. Can search any Beast-Warrior monster that can be Normal Summoned by detaching a material, including other Zoodiac monsters (mainly Whiptail, which can then attach itself to this card to give it 1200 ATK and banish any monster it battles), but it can also search Pendulums, Fire Fists, Bujins, Gladiator Beasts, Koa'ki Meiru, and others; basically like Fire Formation - Tenki.
Zoodiac Drident	Strong Rank 4 Xyz Monster that can easily be Summoned by using any other Zoodiac monster you control as material, including other Zoodiac Xyz Monsters such as Chakanine or Broadbull (also Forbidden), which only require any 2 Level 4 monsters. Can destroy any face-up card on the field during either player's turn, clearing the way for OTKs or allowing disruption during your opponent's turn. Mainly hit due to Zoodiac Decks consistently dominating the metagame for many months.
Butterfly Dagger - Elma	Creates infinite loops with Gearfried the Iron Knight, such as drawing an unlimited number of cards with Royal Magical Library (which can either lead to drawing the pieces of Exodia or dealing massive damage with Chaos Emperor Dragon - Envoy of the End) or gaining an unlimited number of LP with Spell Absorption (which can then lead to an infinite burn loop with Fire Princess), etc. Also insanely abusable in Inzektors.
Card of Safe Return	Many Decks rely on Graveyard manipulation (such as Zombies, Wind-Up, Fabled, Dark World, Infernoid, etc.); this card can easily generate extremely high draw power when used with them. No once-per-turn restriction means that several cards that Special Summon themselves (e.g. Colossal Fighter) can lead to infinite loops, with such results as drawing all five Forbidden One pieces in a single turn.
Change of Heart	Gain an opponent's monster for free for a turn, and you can do whatever you want with it. A superior version of Brain Control and Mind Control.
Chicken Game	Generic draw Spell that can be searched by Terraforming (Limited in the OCG) and reused by Pseudo Space, enabling severe Deck thinning for virtually any Deck. Mainly Forbidden due to abuse in various FTK Decks (including one with Monarchs) that used this card and Upstart Goblin (below) to separate your LP from your opponent's enough to FTK using Life Equalizer (Forbidden in the OCG), Blasting the Ruins, or Magical Explosion (Limited in the TCG). This card is Unlimited in the OCG.
Cold Wave	Disables ALL Spell and Trap usage for a fairly long time, which allows preparations for an OTK and can leave the opponent vulnerable and unable to defend themselves if you wipe out their backrow. Incredibly hard to fight against if the opponent is using a Deck that focuses on monster effects rather than Spells or Traps. Cold Feet was intended to be a fair(ly bad) version of this card.
Confiscation	Devastating 1-for-1 card with a low cost. Allows a player to see an opponent's entire hand (letting them know what Deck they may be playing and what strategies they may use next) and freely get rid of their presumably best or most useful card. Appointer of the Red Lotus was designed to be a fair version of this card.
Delinquent Duo	Very powerful 2-for-1 card with a low cost. Discards 2 cards from your opponent's hand, and they have no control over one of the cards they lose. Especially devastating when the opponent has only a few cards left.
Dimension Fusion	Too many good combos. Was abused with Dark Armed Dragon to clear the opponent's field and swarm your own, forming an OTK. With more and more Decks relying on banished monsters, this can't come back. Like Cyber-Stein (above), the outcome is worth the high cost.
Divine Sword - Phoenix Blade	Has no turn restriction on its recovery effect. Used in most Decks that use Isolde, Two Tales of the Noble Knights, which can dump it into the Graveyard with its Warrior-Summoning effect, and proper Graveyard set-up allows it to be recovered again and again for discard fodder. Used in Gouki Decks to make Topologic Gumblar Dragon in Turn 1 and create devastating hand loops. This card is Unlimited in the TCG.
Dragonic Diagram	A strong Field Spell Card that can search any "True Draco" or "True King" card from your Deck to your hand by destroying any other card you control or in your hand, and can also give all True Draco and True King monsters 300 ATK and DEF while protecting those that are Tribute Summoned from being destroyed by battle once per turn. The destruction effect is not a cost, and can thus trigger the effects of the True Kings and many other archetypes, as well as Dinosaurs. Can be searched by Terraforming (Limited in the OCG) and Metaverse. This card is Unlimited in the TCG.
Giant Trunade	Clears backrow and prepares for OTKs. Harder to stop than Heavy Storm (which is also Forbidden) because it doesn't destroy. Mainly banned for it allowing to recycle and reuse your Spell/Trap Cards with effects that can only be used a limited amount of times while they are on the field. This is notably the reason that effects that consistently bounce your own Spells/Traps are very rare. Hey, Trunade! was designed to be a fair version of this card.
Graceful Charity	Too fast. You draw before you discard. Sets up Graveyard. Although it seems like an even trade, it is often better than Pot of Greed in Decks that like to discard.
Harpie's Feather Duster	Too powerful. Clears out the opponent's backrow while yours is safe. Can be searched by Hysteric Sign. This card is Limited in the OCG.
Heavy Storm	This on the first turn is usually catastrophic for the opponent, and not everyone runs Starlight Road or THRIO. Can even benefit you by clearing up useless space or destroying your own Pendulum Scales so you can trigger their effects, activate more, then Pendulum Summon them back for OTKs, though New Master Rule makes this far trickier to pull off now.
Kaiser Colosseum	Powerful and splashable floodgate that prevents your opponent from Summoning more monsters than you control. Unlike other common floodgate cards, it does not have to be set before activation since it is a Spell, and only directly affects your opponent. Can stop the opponent from being able to play at all if you have just 1 very powerful boss monster like Master Peace, the True Dracoslaying King (Forbidden in the OCG) or Majespecter Unicorn - Kirin (also Forbidden; see above). This card is Unlimited in the OCG.
Last Will	Universal searcher. Mainly was Forbidden for making the extremely fast Turtle FTK; however, Catapult Turtle's errata now makes its effect once per turn. While this card can only Special Summon 1 monster with its effect, it could set up OTKs with Chaos Emperor Dragon - Envoy of the End (although no anymore due to its erratum) or Black Rose Dragon. After activation, its effect can be used any time that turn, even during the Battle Phase.
Mass Driver	Abused in many Decks to form a FTK, since it does not use up the Normal Summon and can be used multiple times a turn. Finishing move.
Metamorphosis	Was a key part of the Goat Control Deck and has too many good combos. Notable ones include Beast King Barbaros → Cyber Twin Dragon/Blaze Fenix, the Burning Bombardment Bird and Metal Reflect Slime/Tragoedia/REDMD → Cyber End Dragon/Destiny End Dragoon/Gaia Drake, the Universal Force/Naturia Exterio. With the introduction of more Level-manipulating cards and easier Summoning, this card is much less likely to come back.
Mirage of Nightmare	Too fast. If it gets destroyed, you don't need to discard, so it can be as good as, if not better than, Pot of Greed. Also combos with Emergency Provisions, Solomon's Lawbook, Gravelstorm, and MST extremely well. Devastating in Dark World and Fabled Decks.
Painful Choice	Gets a good card and/or sends cards that work well in the Graveyard; similar to activating 4 Foolish Burials at once. Instant Graveyard setup for Decks like Plants, Infernity, Dragon Rulers, Zombies, and Chaos Dragons to name a few. With more and more cards that gain advantage when sent to the Graveyard, this card becomes even more powerful.
Pot of Avarice	Recycles the Graveyard while adding draw power. Almost/just as easy to use as Pot of Greed (see below). Excellent in certain Decks, recycling cards like Reborn Tengu, Gadgets, Wind-Ups, etc. Can also put Extra Deck monsters back, leaving you with no Graveyard set-up disadvantage and letting you reuse Limited Extra Deck monsters. Plants abused this card, but the March 2012 lists killed Plant Synchro. Pot of Dichotomy was designed to be a fair version of this card. This card is Unlimited in the OCG.
Pot of Greed	Instantly gives +1 in card advantage to the user for absolutely no cost. Too easy to use (literally every Deck in the game would be improved by adding this card to it). Forcing all competent Decks to run this card to avoid being at a disadvantage would be unfair. Fair versions of this card are constantly being made.
Premature Burial	Fast revival. Formerly looped with Brionac, Dragon of the Ice Barrier (though Brionac has now been errata'd so it can't bounce your own cards) and Giant Trunade, which is also Forbidden. There are also combos that allow 1 Special Summon per turn through cards like Dewloren, Tiger King of the Ice Barrier, Falcon of Mist Valley, etc. Searchable and reusable via Hidden Armory. Overdone Burial was designed to be a fair version of this card.
Rank-Up-Magic Argent Chaos Force	Forbidden due to abuse in quickly Summoning Number S0: Utopic ZEXAL to lock down the opponent. As it can return itself to the hand from the GY, it can be easily sent to the Graveyard by effects like Beatrice, Lady of the Eternal (Limited in the TCG) and Foolish Burial Goods, then returned to the hand by Special Summoning a Rank 5 or higher monster (easily accomplished by using Beatrice as material to Xyz Summon Gaia Dragon, the Thunder Charger). This card is Unlimited in the OCG.
Snatch Steal	Gives near permanent control. Opponent's LP gain can be avoided entirely by either stealing a strong monster and consistently attacking, or using it as material/Tribute. Searchable and reusable via Hidden Armory. Almost as, if not more powerful than, Change of Heart (see above).
Soul Charge	Revives any number of monsters from your Graveyard for easy Synchro/Xyz/Link Summons in almost every Deck. While it has an LP loss correlative to the number of revived monsters (if you're reviving fewer monsters, you lose less LP, if you're reviving more monsters, you lose more LP), and isn't a cost you can dodge with other cards, these restrictions are usually offset by the large field advantage offered. Forces you to skip Battle Phase, but is often used on the first turn, so the player isn't affected. Has only grown more powerful with the onset of Links, with this being an extraordinarily easy Extra Link with a few of the right cards in your Graveyard. This card is Limited in the OCG.
Spellbook of Judgment	One of the most broken Spell Cards ever made. An incredible searcher for Prophecy Decks, adds several Spellbook Spell cards from your Deck to your hand during the End Phase of the turn it was activated, like Secrets, Master, Power, Fate, Wisdom, Life, Eternity, Star Hall, and Tower; for every Spell Card played. Last effect Summons great Spellcasters depending on the number searched, such as Jowgen the Spiritualist (seals Special Summons), Kycoo the Ghost Destroyer (prevents Banishing), Maiden with Eyes of Blue (stuns opponent), Justice of Prophecy (who then searches another Spellbook and High Priestess of Prophecy), Dark Magician of Chaos (who can then retrieve any Spell), and even World of Prophecy (can act like a nuke). Can be searched easily itself with Secrets, Master (copying Secrets), Spellbook Magician of Prophecy, Spellbook Library of the Crescent, and Justice of Prophecy. Can be reused with Tower, Magician of Faith (in the TCG), DMoC, Eternity (after banished with Spellbook of Fate or High Priestess of Prophecy), or Master (copying Eternity).
Super Rejuvenation	Amazing draw card. Makes strong discard-and-draw cards even stronger. Offsets the costs of certain card effects. Can draw out most of your Deck in one turn if used right since it can be used multiple times per turn. Abusable in Exodia, Hieratic, and Dragon Ruler Decks. Trial and Tribulation was designed to be a fair version of this card. This card is Unlimited in the OCG.
That Grass Looks Greener	Powerful, costless Graveyard set-up card that instantly sends cards from your Deck to the Graveyard until you have the same number of cards in your Deck as your opponent. Similar to Monster Gate and Reasoning (both Limited), but can be better since there is more control over the number of milled cards. Mainly hit due to abuse in 60-card Decks that focus heavily on Infernoids, Paleozoics, and Fairy Tail - Snow (also Forbidden in the TCG) since it can instantly send 20 cards from your Deck to your Graveyard against most other Decks that run only 40 cards. Can be searched by Left Arm Offering. This card is Semi-Limited in the OCG.
The Forceful Sentry	A Confiscation (above) with no cost. Returns the card to the Deck rather than discarding it to the Graveyard. Having a card in the Graveyard is usually considered to be better that having it in the Deck. The Humble Sentry was intended to be a fair(ly bad) version of this card.
The Phantom Knights' Rank-Up-Magic Launch	Quick-Play "Rank-Up-Magic" that Ranks-Up any DARK Xyz with no materials into any DARK Xyz that is 1 Rank higher. Can Summon lockdown monsters like D/D/D Duo-Dawn King Kali Yuga, True King of All Calamities, or Outer Entity Azathot to prevent the opponent from activating effects on their own turn. "Azathot" is easily Summoned with Time Thief Winder, which can banish itself from the field and then return with no materials. Unlike most Rank-Up-Magics, this card is easily searched and/or recovered. This card is Unlimited in the OCG.
Zoodiac Barrage	Can Special Summon any Zoodiac monster from your Deck by destroying ANY face-up card you control, even itself, Fire Formation - Tenki, or Tensu after they've been used, and can also attach itself to a Zoodiac Xyz Monster if it is destroyed, even by its own effect. Banned due to Zoodiacs creating Tier 0 formats and being an easy material in general that works well with any card that triggers on being destroyed. This card is Unlimited in the TCG.
Last Turn	Turns around the game with little to no effort. Overwhelmingly flexible with various Decks and monsters. An instant win is guaranteed when you control a monster that prevents your opponent from Special Summoning OR can create an instant DRAW. Easy to get down to 1000 or less LP with cards like Wall of Revealing Light, Inspection, and Backs to the Wall.
Life Equalizer	This card forms OTKs with cards such as Magical Explosion (also Forbidden in the OCG) and Blasting the Ruins, and its apparently steep requirement can easily be met with cards such as Chicken Game (Forbidden in the TCG), Upstart Goblin, and Wall of Revealing Light. This card is Unlimited in the TCG.
Magical Explosion	Crux of the Magical Explosion FTK. Simply requires you to dump Spells in your Graveyard and empty your hand (not a challenge in several Deck types) to be deadly, especially with more than one available. Was initially Limited to cripple the consistency of the FTK, then Forbidden many years later in the OCG after abuse in Sky Striker strategies. This card is Limited in the TCG.
Return from the Different Dimension	Similar to Dimension Fusion (above). Creates very easy OTKs, especially in Dragon Ruler Decks. Easy to prevent the monsters from being banished again since you can just Synchro/Xyz/Link Summon with them.
Royal Oppression	One card to continuously stop a large number of cards and cripple a large number of Decks with a fairly low cost. Some Decks abuse the fact that it cannot be used in the Damage Step. Can stop a larger variety of cards than Solemn Warning, which has a larger cost and can only be used once. Used in swarm Decks, where you would spam a lot of big monsters, and then flip this over.
Self-Destruct Button	Mainly Forbidden for causing too many DRAWs in Tournaments and messing up Ranked Games. This card is Unlimited in the OCG.
Sixth Sense	Potentially one of the strongest forms of draw power, being able to net 6 cards from one effect. The drawback is also potentially beneficial, especially with more Graveyard-reliant Decks. The drawing aspect can be rigged with That Six.
Time Seal	Forces the opponent to skip a Draw Phase, which is lethal when they are topdecking. Unlike Drastic Drop Off, this card can be chained anytime, making it much better; also with Mask of Darkness and Tsukuyomi at 3, lockdown Decks could take unfair advantage.
Trap Dustshoot	Devastating to the opponent if played on them during their first turn. Broken when combined with other Traps like Mind Crush. If used early on, it creates a situation where your opponent will have a lot of trouble recovering. Many thought that the opponent having to have at least 4 cards in their hand was too fair a restriction to ban it. But, it is horrible to go against in Turn 1.
Ultimate Offering	A cheap way to swarm the field, resulting in easy Xyz/Link Summons. Gadgets can spawn Rank 4s like crazy (as well as Rank 5s with Gear Gigant X and Jumbo Drill around). The effect used to be that both players could use the effect, but it was errata'd so only the controller of the card can, which gives a huge advantage. Also abusable in various other Decks such as Madolche, Blackwing (when comboed with Black Whirlwind), and Empty Jar.
Vanity's Emptiness	One card that can continuously stop a large number of cards and cripple a large number of Decks with no cost. While it is easily destroyed when another card is sent from your Deck or field to your Graveyard, this can sometimes work in the user's favor when something deliberately sends a card to your Graveyard (e.g. activating Mystical Space Typhoon on an opponent's card) so you can keep Special Summoning on your turn. Pendulum Decks also circumvent its downside by going from the field to your Extra Deck instead, opening it up to further abuse. This card is Limited in the OCG.
Limited
Altergeist Multifaker	Very easily Special Summoned, requiring only the activation of a Trap Card (such as Personal Spoofing), and pulls a monster from the Deck for an instant Altergeist Hexstia, which can negate any opponent's Spell/Trap Card. This card is Unlimited in the TCG.
Armageddon Knight	Sends ANY DARK monster from your Deck to the Graveyard whenever it's Summoned. Can lead to crazy power-plays just by simply dumping one certain monster and can trigger monster effects like Archfiend Heiress, Elemental HERO Shadow Mist, and all the Shaddoll monsters. Can be searched by Reinforcement of the Army, Mystic Tomato, and Summoner Monk. Saw heavy use as a "1-card FTK" in late 2018, whereby this card dumping Malicious (Semi-Limited in the TCG) quickly Summoned Isolde, Two Tales of the Noble Knights, which soon led to Firewall Dragon (Forbidden).
Babycerasaurus	Generates excellent advantage when triggered by Dragonic Diagram (Forbidden in the OCG), Lost World, Miscellaneousaurus (Limited in the TCG), Souleating Oviraptor (Limited in the OCG), and "True King Lithosagym, the Disaster" (Forbidden in the TCG). Easily searched by Souleating Oviraptor and Fossil Dig (Semi-Limited in the OCG). This card is Unlimited in the TCG.
Beatrice, Lady of the Eternal	Very good Rank 6 Xyz Monster with a fantastic effect. Can easily be Xyz Summoned in Burning Abyss Decks by using Dante, Traveler of the Burning Abyss (Limited in the OCG) as Xyz Material (albeit with the downside of its Quick Effect not being usable that turn), and can send any card from your Deck to the Graveyard during either player's turn, allowing you to search out Limited cards like Graff or Cir, or interrupt your opponent's plays by sending Farfa, Alich, or Mischief of the Gnomes from your Deck to the Graveyard. It can also replace itself with Dante, Pilgrim of the Burning Abyss when it dies. Even more abusable in non-Burning Abyss Decks since its Quick Effect can be used right away, and even chained to cards like Bottomless Trap Hole, Compulsory Evacuation Device, and Torrential Tribute. It can also mill Rank-Up-Magic Argent Chaos Force (Forbidden) to be added to the hand to easily Summon Number S0: Utopic ZEXAL. This card is Unlimited in the OCG.
Blaze Fenix, the Burning Bombardment Bird	Very powerful Fusion Monster with a deadly burn effect. Creates easy OTKs/FTKs when used in conjunction with cards like Ancient Fairy Dragon, Black Garden, and Fusion Gate; or with Elemental HERO Electrum, Fusion Gate, and Chain Material. This card is Unlimited in the TCG.
Chaos Emperor Dragon - Envoy of the End	Can be Special Summoned easily, great effect, high ATK, deadly nuke, and serious burn. Sends cards rather than destroying, thus cards like Stardust Dragon and Starlight Road cannot stop it. Previously, if you used its effect while you controlled a monster like Sangan, you could easily gain an advantage over your opponent since they would be topdecking and you would have a monster. However, it has since received an errata which makes it a Nomi monster, inflicts damage based on only the opponent's cards, and prevents other card effects from being activated for the rest of the turn. Was a key card in the infamous Yata-Garasu Lockdown. Can be searched by Eclipse Wyvern. This card is Unlimited in the OCG.
Chronograph Sorcerer	First monster effect is easy to trigger by destroying your own cards (see: Heavymetalfoes Electrumite), and brings out 2 monsters to do what you wish with. Pendulum Effect effectively brings out a new Link Material from the Deck, and can allow another Chronograph to activate its effect too. This card is Unlimited in the TCG.
Cir, Malebranche of the Burning Abyss	Key card in Burning Abyss. Can Special Summon any of their monsters from your Graveyard whenever it is sent to the Graveyard, allowing easy recovery, or to Summon another Dante, Traveler of the Burning Abyss, Virgil, Rock Star of the Burning Abyss, or get set-up for Fire Lake of the Burning Abyss again in the mid- to late-game. Can be searched by Tour Guide from the Underworld and Graff, Malebranche of the Burning Abyss (both Limited in the TCG). This card is Unlimited in the OCG.
Crystron Needlefiber	The third part of an "Unholy Trinity" of powerful Links, which also includes Firewall Dragon and Summon Sorceress. Easily Link Summoned with almost any method that allows you to Special Summon a Tuner (Blackwing - Steam the Cloak, Glow-Up Bulb, even something like Instant Fusion into Sea Monster of Theseus...). Immediately climbs into Summon Sorceress with its first effect. Second effect can also be used as an easy way into a Tuner Synchro Monster such as Shooting Riser Dragon or T.G. Wonder Magician. This card is not yet released in the TCG, likely for the same reason it was Forbidden.
Cyber-Stein	Can lead to easy OTKs with Fusions like Blue-Eyes Ultimate Dragon, Cyber End Dragon, or Cyber Twin Dragon equipped with Megamorph; or to an instant lockdown with Naturia Exterio or The Last Warrior from Another Planet. If the effect goes through, it's devastating. Can be searched easily by Gear Gigant X. However, the cost, compared to alternative options, is steep at 5000 LP, though it can be circumvented with combos like DNA Surgery (calling Psychic) + Brain Research Lab/Telekinetic Charging Cell. This card is Semi-Limited in the OCG.
Dark Armed Dragon	Can be Special Summoned easily in most DARK Decks. Specific destructive power. High ATK. See DAD Return and Tele-DAD. This card is Semi-Limited in the OCG.
Dark Grepher	Easily Special Summoned, so easy Link Material. Used as an alternative option to Armageddon Knight (also Limited in the TCG), to set up various Warrior-based engines leading to whatever powerful boss monster you desire. Better in some ways than Arma, as it doesn't eat the Normal Summon and its discard costs can be turned into advantage when using Danger! cards. This card is Semi-Limited in the OCG.
Deep Sea Diva	Good searcher. Creates automatic Level 5-8 Synchros or Rank 2 Xyz when used in conjunction with Abyss-sphere and Atlantean Marksman or Atlantean Heavy Infantry upon Normal Summon.
Dewloren, Tiger King of the Ice Barrier	Creates loops and OTKs when used with cards like Symbols of Duty or Symbol of Heritage (Limited). Used to be Summoned easily using Elder Entity Norden (Forbidden) as Synchro Material. Can also reuse cards like Call of the Haunted, Fiendish Chain, Abyss-sphere, etc.
Dinomight Knight, the True Dracofighter	Allows easy searching and/or activation of True Draco and True King Continuous Traps directly from your Deck, without needing to be set first, all of which allow the player to Tribute Summon another True Draco during the opponent's turn on top of their other powerful effects. Because this effect is not an only-once-per turn, this means that multiple Dinomight can activate their effects in one turn. Previously Forbidden, but has slid down the list due to Master Peace, the True Dracoslaying King being Forbidden. This card is Unlimited in the OCG.
Ehther the Heavenly Monarch	Key monster in Monarch Decks. Can Special Summon another Monarch from your Deck when it's Tribute Summoned, while also setting up your Graveyard with cards such as Pantheism of the Monarchs or The Prime Monarch. It can even Tribute Summon itself during the opponent's turn to disrupt their plays with The Monarchs Stormforth and Kuraz the Light Monarch. This card is Unlimited in the OCG.
El Shaddoll Construct	Key Fusion Monster in Shaddoll Decks along with El Shaddoll Winda (below). Sets up combos by sending ANY "Shaddoll" card from your Deck to the Graveyard once Fusion Summoned, can send useful LIGHT monsters from the Deck to the Graveyard when using "Shaddoll Fusion", and can autokill any Special Summoned monster when it battles. This card is Unlimited in the OCG.
Elemental HERO Shadow Mist	Good Level 4 monster in HERO Decks that can search any "Change" Quick-Play Spell Card (mainly Mask Change or Mask Change II) when it's Special Summoned and can also search a HERO monster when it's sent to the Graveyard. Was Limited in OCG due to the unexpected splashability in most Decks. This card is Unlimited in the TCG.
Elemental HERO Stratos	Great searcher that triggers on Normal or Special Summon. No once-per-turn restriction allows it to create OTKs. You lose no advantage playing this card. Easily searched by other cards, such as A Hero Lives (Limited in the TCG), E - Emergency Call, Reinforcement of the Army (also Limited), Summoner Monk, etc. Also has a potent destruction effect. Was part of the Airblade Turbo Deck, the top Deck of the September 2006 Format. This card is Unlimited in the OCG.
Evigishki Gustkraken	Awesome hand control card. There is a loop where this card is used within a Gishki-Hieratic hybrid Deck and can be bounced repeatedly with Constellar Ptolemy M7 to shut down the opponent's hand. It didn't help that Hieratics Summon Level 6 monsters with the greatest of ease. This card is Unlimited in the OCG.
Evigishki Mind Augus	Can greatly hinder opponent's Graveyard while recycling yours, letting you reuse your Gishki cards. Key card of the Gishki FTK. This card is Unlimited in the OCG.
Exodia the Forbidden One	Instant win card. You don't need to be lucky to get it. With more and more stall and draw cards being released, these will stay Limited. Although unlikely, if 1 of the pieces becomes Forbidden, then the other 4 can be Unlimited.
Left Arm of the Forbidden One
Left Leg of the Forbidden One
Right Arm of the Forbidden One
Right Leg of the Forbidden One
Gem-Knight Master Diamond	Can copy the effects of other Gem-Knight monsters, most importantly Gem-Knight Lady Lapis Lazuli to create a burn FTK. After the release of Gem-Knight Phantom Quartz, an FTK combo could be started with just Brilliant Fusion and any Gem-Knight monster in the starting hand. This card is Unlimited in the OCG.
Genex Ally Birdman	An universal Tuner that can be Special Summoned easily. Creates loops and even OTKs generating lots of monsters in Karakuris, Agents, Hieratics, and other Decks if used right. Combos very well with Divine Wind of Mist Valley (which is also Limited). Also part of the Gallis OTK and Divine Wind FTK.
Graff, Malebranche of the Burning Abyss	Can Special Summon any Burning Abyss monster from your Deck whenever it's sent to the Graveyard, allowing you to Xyz Summon another Dante, Traveler of the Burning Abyss, Synchro Summon Virgil, Rock Star of the Burning Abyss, or set-up for Fire Lake of the Burning Abyss. Can be searched by Tour Guide from the Underworld (also Limited in the TCG; see below) and reused by Cir, Malebranche of the Burning Abyss (also Limited in the TCG) or Dante. This card is Unlimited in the OCG.
Harmonizing Magician	Pendulum Tuner with a strong effect, and key in Pendulum Magicians. On Pendulum Summon, brings out a Pendulum Magician for free Synchro/Xyz/Link Material, an effect which wasn't made any less powerful in New Master Rule thanks to this strategy not requiring Link Monsters. Notably, doesn't have any restriction on being used as a Link Material. This card is Unlimited in the TCG.
Heavymetalfoes Electrumite	Generic Link Monster with superb effects for Pendulum Decks, including Pendulum Magicians. Its effects can all play off each other. Quickly brings key Pendulum Monsters straight into play, including Double Iris Magician and Astrograph Sorcerer (both Limited in the OCG and Forbidden in the TCG), both of which can allow serious power plays. Also capable of looping Astrograph.
Ignister Prominence, the Blasting Dracoslayer	This card can eliminate any opponent's card for free thanks to its second effect while getting around cards that are immune to targeting and/or destruction. Its second effect also fuels the Summon of Dinoster Power, the Mighty Dracoslayer and Majester Paladin, the Ascending Dracoslayer, which can lead to more branching plays. This card is Unlimited in the OCG.
Infernity Archfiend	The key to Infernity Decks. Can be Special Summoned easily by its own effect or through cards such as Stygian Street Patrol or Summoner Monk. Searches any Infernity card from your Deck when Special Summoned. No once-per-turn restriction allows it to create OTKs and net multiple searches. This card is Unlimited in the OCG.
Invoked Mechaba	Semi-generic, universal negator that is easy to Summon in several Deck types. Can be brought out quickly by Aleister the Invoker (Semi-Limited in the OCG) searching Invocation. Banishes the negated card rather than just destroying it, often neutralizing it for good. Can lead to lockdowns without much effort. This card is Unlimited in the TCG.
Inzektor Dragonfly	This one card can swarm the field AND cause nasty loops in one turn with Inzektor Hornet, Inzektor Ladybug, Inzektor Hopper, or Inzektor Earwig. Second effect can be used multiple times in one turn to create OTKs. Can be searched easily with Sangan (now errata'd), Howling Insect, Insect Imitation or Transmodify (when used on Inzektor Ladybug), Inzektor Centipede, and Mystic Tomato. Can be reused with Inzektor Giga-Mantis or Inzektor Sword - Zektkaliber. This card is Unlimited in the OCG.
Lady Debug	Searches any Level 3 or lower Cyberse when Normal or Special Summoned. Used in Salamangreats, where Gazelle (also Limited in the OCG) is both a valid target for its search effect as well as Link Material for Balelynx, allowing Gazelle to Special Summon itself. Hit to limit the consistency of the Deck.
Lonefire Blossom	Search and Special Summon ANY Plant; this includes Sylvans, Tuners, Dandylion, Mystic Tomato, Tytannial, Princess of Camellias, Gigaplant, etc. Doppel-Plants and quite a few other Plant Decks were also topping tournaments for a long time. Formerly abused in Synchrocentric. Returned to the list after the rise of various different Plant FTKs in Link Format in the OCG. This card is Unlimited in the TCG.
Luster Pendulum, the Dracoslayer	Key card in the Dracoslayer engine. Can destroy any card in your other Pendulum Zone and search another copy of it, providing you with more resources. Can trigger the effects of cards such as Performage Plushfire (Forbidden) or Guiding Ariadne. Can be searched easily itself with Draco Face-Off, Ignister Prominence, the Blasting Dracoslayer (Limited in the TCG), or Majester Paladin, the Ascending Dracoslayer. This card is Semi-Limited in the TCG.
Mathematician	Splashable Level 3 monster with advantage-generating effects. Can send any Level 4 or lower monster from your Deck to the Graveyard when Normal Summoned, typically one that can be revived by its own effect. Lets you draw a card when it dies in battle. Combos well with Graveyard-focused Decks, such as Shaddolls. Can also be used with Felis, Lightsworn Archer to easily Synchro Summon Black Rose Dragon or Arcanite Magician. Used to easily trigger the effect of Dandylion (Forbidden) for a quick Link-2. This card is Unlimited in the TCG.
Morphing Jar	High draw power. Messes up opponent's hand. Sets up Graveyard. However, the opponent can also abuse this. Has its own OTK/FTK Deck. Can also cause an OTK/FTK with Jackpot 7.
Necroface	Macro Decks of any sort LOVE this card. Has the potential of being a powerful beater and resets and/or sets up banished cards. Abusable with Gold Sarcophagus, Allure of Darkness, and Pot of Desires. Combined with Soul Absorption is a free 5500 LP gained when banished. Having multiple copies can loop them, chain their own effects when banished from the Deck, or make OTKs (Necro Mill OTK). Combos EXTREMELY well with Inferno Tempest, Shiranuis, and PSY-Framelord Omega (below). This card is Semi-Limited in the TCG.
Nekroz of Unicore	Key card in Nekroz. Can negate the effects of any monster Special Summoned from the Extra Deck, and can recycle any Nekroz card from the Graveyard. Combos extremely well with Nekroz Kaleidomirror to send Herald of the Arc Light from your Extra Deck to the Graveyard to search out any Ritual Monster or Ritual Spell from your Deck.
Night Assailant	Must be at 1, otherwise one copy can just recycle another when discarded and an infinite loop will be created, which would lead to cards like Snipe Hunter wiping out the whole field, Dark Crusader having unlimited ATK, etc.
Performage Damage Juggler	Insanely splashable utility. Key card in Performage Decks. Can negate burn effects or stop OTKs from hand while providing crazy consistency to any Deck running Performages from Graveyard. Mainly hit due to Performage Performapal (PePe) Decks that were topping everywhere. This card is Unlimited in the OCG.
Phantom Skyblaster	Special Summons Skyblaster Tokens when Normal or Flip Summoned up to the number of monsters you control. An instant Link-2 upon Normal Summoning, and potentially a Link-3 or -4 if you control another monster when this card is Normal Summoned. This card is Unlimited in the OCG.
Predaplant Ophrys Scorpio	Quickly introduces 2 Plant monsters into play, with the extra monster on the field allowing for a quick 1-card Fusion/Xyz/Link Summon. Dumps whatever monster you want in the Graveyard as cost. Opening move of the FTK involving Phoenixian Cluster Amaryllis (Forbidden). Its main target to Summon is almost always Predaplant Darlingtonia Cobra, which searches Instant Fusion and Brilliant Fusion, setting up other FTKs (and, for good measure, providing valid material for M-X-Saber Invoker). This card is Unlimited in the TCG.
PSY-Framelord Omega	Amazing Level 8 Synchro Monster that can banish itself and a card in the opponent's hand during either player's Main Phase, return a banished card to the Graveyard during the opponent's Standby Phase, and can even recycle itself and one other card in either player's Graveyard during your Main Phase. Mainly hit due to a hand loop in the OCG involving Synchro Summoning 3 copies of this card in one turn to banish 3 cards in your opponent's hand. Abusable in other Decks like Zombies, Infernoids, and ABCs. Its ability to remove itself from the field also makes it potent under the New Master Rules since it frees up an Extra Monster Zone it may occupy for absolutely no effort.
Qliphort Scout	Adds any "Qli" card from your Deck to your hand once per turn, by paying 800 LP. Since that's just its Pendulum Effect, it's also treated as a Normal Monster so it can be searched easily itself via Summoner's Art, or with Saqlifice (Limited). This card is Unlimited in the OCG.
Ritual Beast Ulti-Cannahawk	Key Fusion Monster in Ritual Beast Decks. Can search any Ritual Beast card. Generates huge card advantage by repeatedly fusing and de-fusing to use its effect multiple times. At 1, it's much easier to permanently eliminate this card. Additionally, it effectively prevents Spiritual Beast Rampengu from searching out Spiritual Beast Cannahawk, another key searcher. This card is Unlimited in the OCG.
Salamangreat Gazelle	Key card in Salamangreats. Summoned when a Salamangreat monster is sent to the Graveyard by any means, which is usually done by Link Summoning Salamangreat Balelynx (thereby searching Sanctuary). On Summoning, allows the user to dump any Salamangreat card they desire, making it highly versatile in the Deck. This card is Unlimited in the TCG.
Shurit, Strategist of the Nekroz	Key card in Nekroz. Can be used to easily Ritual Summon the otherwise difficult to Summon higher-Level Nekroz Ritual Monsters, and even searches any Warrior-Type Nekroz Ritual Monster on top of that. Can be searched easily with Nekroz of Brionac or Reinforcement of the Army and reused by Nekroz of Unicore or Dance Princess of the Nekroz (after banished by Nekroz of Valkyrus or one of the Nekroz Ritual Spell Cards). However, Nekroz sees little use nowadays. This card is Unlimited in the OCG.
Sky Striker Ace - Kagari	Link-1 with a strong effect. Recovers any Sky Striker Spell, which is usually Hornet Drones, Engage!, or Widow Anchor, which due to lacking any once-per-turn restriction can all be immediately put to use again.
Souleating Oviraptor	Searches or dumps any Dinosaur of your choice, and can revive any Dinosaur by destroying another; if destroying Babycerasaurus (Limited in the OCG) or Petiteranodon, this can generate even more advantage for Synchro, Xyz, and Link Summons. Can search Double Evolution Pill by dumping Overtex Qoatlus. An instant Level 5 Synchro or Link-2 when combined with Miscellaneousaurus and Jurrac Aeolo. This card is Unlimited in the TCG.
Speedroid Terrortop	Can Special Summon itself when you have no monsters, then search Speedroid Taketomborg, which also Special Summons itself, letting you make a Rank 3 Xyz Monster with 1 card without using your Normal Summon. Common choices include M-X-Saber Invoker and Dante, Traveler of the Burning Abyss to kick-start combos, and Totem Bird for disruption. Can also search other Speedroid monsters, such as Red-Eyed Dice, which can be used for Synchro plays.
SPYRAL GEAR - Drone	Key card in SPYRALs. Rearranges the top 3 cards of the opponent's Deck upon being Summoned, eliminating any guesswork on the player's part for big plays, unless your opponent plays a searcher immediately afterwards. Can Tribute itself to permanently boost the ATK of a SPYRAL by 500 for each card your opponent controls, even during the Damage Step. Lastly, it can banish itself and another SPYRAL card from your Graveyard to retrieve SPYRAL Super Agent, preparing set-up for future plays. This card is Unlimited in the OCG.
SPYRAL Quik-Fix	When combined with SPYRAL Double Helix, Inferno Reckless Summon, and especially Machine Duplication, this card is able to create some insane combos and loops. At 1, it's much easier to permanently eliminate this card. Additionally, it effectively prevents circumvention of its self-banishment effect by using it as Xyz Material after revival, as the only other monster in the Deck with the same Level is SPYRAL GEAR - Drone (also Limited in the TCG). This card is Semi-Limited in the OCG.
Supreme King Dragon Darkwurm	Its Special Summoning effect is used in Pendulum Magicians and several other Pendulum focused Decks as a way to get Heavymetalfoes Electrumite out easily without using the Pendulum Summon, which enables plays involving Double Iris Magician (also Limited in the OCG and banned in the TCG). This card is Unlimited in the TCG.
Thunder Dragon Colossus	Thunder Dragons' de-facto boss monster. Easy to Summon, requiring only the Tribute of 1 Thunder monster during the turn a Thunder monster's hand effect was activated (which for TDs means "any turn"). Locks down the opponent from searching, which cripples most modern Decks. Can protect itself from destruction by banishing a Thunder monster from the Graveyard - which then activates the on-banish effects of the TDs used to get it on field. Having more than one on field pretty much guaranteed your opponent can never recover. This card is Unlimited in the TCG.
Thunder Dragonhawk	Thunder Dragons' primary extender. Special Summons any TD from the Graveyard by discarding, creating combos that lead to multiple Thunder Dragon Colossus on field for a lockdown. At 1, it's far less consistent. This card is Unlimited in the TCG.
Tour Guide From the Underworld	Good Searcher. Quickly Summons Rank 3 Xyz Monsters by Summoning another copy of itself or another Level 3 Fiend monster. Good monsters it was used to quickly Summon include Leviair the Sea Dragon, Number 17: Leviathan Dragon, Wind-Up Zenmaines, and Number 30: Acid Golem of Destruction. It saw little use after Sangan, this card's main target, got Forbidden, so it came off the list, but was put back on the list later due to abuse in the Burning Abyss archetype in the TCG, where it can Summon almost any Burning Abyss monster from your Deck to easily make Dante, Traveler of the Burning Abyss.
Trishula, Dragon of the Ice Barrier	Probably the best Synchro around. Easy to drop in most Synchro-based Decks. Banishes a card from 3 different places without targeting. Agents could also drop it easily. Could be looped in Infernities, but now the key cards used to do that are a non-factor (Brionac is errata'd and Daigusto Emeral is Forbidden). This card is Semi-Limited in the OCG.
Zoodiac Ratpier	Instant +1. When attached to a Zoodiac Xyz Monster, that monster can Special Summon another copy of this card by detaching a material. As it is not once per turn, it can be re-used by Summoning another Zoodiac Xyz Monster on top of the old one, re-attached with Zoodiac Tigermortar, and recycled with Zoodiac Combo. When two others are Summoned by its effect, it allows for easy Rank 4 Xyz Summons, such as Brotherhood of the Fire Fist - Tiger King, Daigusto Emeral, or Bujintei Kagutsuchi, while the original usually ends up as Zoodiac Drident (now Forbidden). Can be searched by M-X-Saber Invoker, Zoodiac Broadbull (both Forbidden), Fire Formation - Tenki, or Zoodiac Barrage (Forbidden in the OCG).
A Hero Lives	Generates OTKs, with a cost you can always pay. Can be used with Elemental HERO Stratos (also Limited in the TCG), who then searches for Elemental HERO Bubbleman, to swarm the field without using the Normal Summon. Reintroduced to the list in the TCG to limit the impact of Stratos returning. This card is Semi-Limited in the OCG.
Book of Moon	One of the best anti-meta cards in the game. Stops just about everything and is one true Swiss Army Knife card. With Ignition Effect Priority being revoked, Book of Moon can easily render these monsters harmless and vulnerable by immediately responding to their Summons. It can also benefit you by flipping your monsters back face-down (See Empty Jar). This card is Unlimited in the OCG.
Brilliant Fusion	An FTK generator and engine all in one card. Most often used to bring out Gem-Knight Seraphinite using only monsters from the Deck, and get an extra Normal Summon for whatever you desire, plus Link Material when you don't need her anymore. Previously used in the Gem-Knight FTK involving Master Diamond. Works strongly with Thunder Dragons. This card is Unlimited in the OCG.
Card Destruction	Sets up your hand and Graveyard. Can mess up, or help with, the opponent's hand, but can also set up their Graveyard. Works very well with Dark World, Fabled, and Danger!. Like Morphing Jar (also Limited), can be more devastating to your opponent and more beneficial to you.
Chain Strike	Inflicts massive damage if used right. Key card of Chain Burn Decks such as Chain Strike OTK, which use high numbers of chainable Spells/Traps to achieve ludicrous damage. This card is Semi-Limited in the OCG.
Dark Hole	Powerful and with no cost, but floating effects, Starlight Road and The Huge Revolution is Over make it harder to play, and Raigeki is often preferred over it. This card is Unlimited in the OCG.
Dimensional Fissure	Good counter to Graveyard-reliant Decks like Dark World. Similar to Macro Cosmos, which is also Limited. Some Decks abuse the mechanics of this card. This card is Unlimited in the OCG.
Divine Wind of Mist Valley	Special Summons any Level 4 or lower WIND monster from your Deck if a WIND monster returns to the hand. Creates loops at more than 1 when combo'ed with Ancient Fairy Dragon. Works well with Genex Ally Birdman (Limited) and Harpie Dancer. Can be searched easily with Terraforming (Limited in the OCG). Key card of the Divine Wind FTK.
Draco Face-Off	A versatile card that easily sets up a Dracoslayer Pendulum Scale OR Special Summon a Level 4 Dracoslayer monster for further plays while setting up Pendulum Summons. It can easily tutor Luster Pendulum, the Dracoslayer, which further aids Pendulum Summons while triggering the effects of monsters such as Guiding Ariadne. Since it is a Quick-Play Spell, it can also steal wins during the Battle Phase.
Emergency Teleport	A versatile search card that Summons Level 3 or lower Psychic-Type Monsters for easy Synchro Summons, Low-Level Kozmo monsters which can then banish themselves on the fly to Summon stronger ones from your hand, and Super Quantum Blue Layer for both pure and hybrid Super Quant Monarch Decks, which were topping in the OCG. This card is Semi-Limited in the OCG.
Final Countdown	Powerful alternate win-condition Spell card. Instantly wins the Duel in 20 turns (or 10 of your turns) if you can stall your opponent long enough with cards like Waboku, Threatening Roar, Battle Fader, Swift Scarecrow, Frozen Soul, Thunder of Ruler or One Day of Peace (which is also Limited). Gold Sarcophagus can get this card to your hand easier. This card is Unlimited in the OCG.
Foolish Burial	Sends any monster you want from the Deck to the Graveyard. Since several Decks depend greatly on Graveyard plays, with the number increasing as the game has developed, this card has only become more powerful. Works well with cards like Wulf, Lightsworn Beast, Plaguespreader Zombie, etc.
Gateway of the Six	Can gain counters whenever a Six Samurai monster is Normal or Special Summoned. With the introduction of Legendary Six Samurai monsters that can Special Summon themselves, and the ability for Gateway to remove Bushido Counters from anywhere on your side of the field, 2 or more of these would result in constant searching of Six Samurai monsters for every Summon. Can create ridiculous swarming, loops, lockdowns, and even FTKs if you control other cards that gain Bushido counters on the field. However, Six Samurais haven't been relevant in a long time, so it came back to 1. This card is Unlimited in the OCG.
Gold Sarcophagus	Allows you to banish any card you want from your Deck, which is an easy search in Decks that manipulate banishment. The 2-turn wait to bring the card back into your hand would balance it if there weren't so many ways to get a banished card into a usable position. Abusable with the Dragon Rulers (Forbidden) and cards such as Necroface, and more recently in Thunder Dragons. Its Limiting, in the OCG, also limits the impact of Tempest's return at 1.
Infernity Launcher	Easily searched by Infernity Archfiend (Limited in the TCG). Creates loops at more than 1. First effect allows you to empty your hand to prepare for its second effect.
Interrupted Kaiju Slumber	Similar to Dark Hole, but can also Special Summon as many Kaiju monsters as possible to either player's field, allowing for multiple different combos and OTKs. Prior to the errata of the latter, it allowed for an easy 3300 damage by Special Summoning Super Anti-Kaiju War Machine Mecha-Dogoran to the opponent's field. Can also search any Kaiju on a later turn for spot removal, and be searched by The Kaiju Files. This card is Unlimited in the TCG.
Magical Mid-Breaker Field	A superb stall card which slows games to a crawl. Various effects that target monsters on the opponent's field are unable to go off, disrupting combos. Used by Extra Link-focused Decks for an even greater level of protection. When you build a Deck around it, the opponent's Deck is affected and yours is not. Can be searched by Terraforming and the like. This card is Unlimited in the OCG.
Mask Change II	This card allows the player to Summon powerful Masked HERO Fusions such as Masked HERO Dark Law or Masked HERO Acid using non-HERO monsters, and its drawback is easily circumvented by using Burning Abyss monsters. This card is Unlimited in the TCG.
Monster Gate	Has the potential to set up the Graveyard with a large number of monsters. Used a lot by Turbo and OTK Decks. Abusable in Hieratics and Infernoids. This card is Unlimited in the OCG.
Monster Reborn	One of the most powerful Spell Cards in the game that can fit into any Deck. Can be a very powerful topdeck with very little setup. Can even Special Summon from the opponent's Graveyard, further punishing them if you manage to destroy a strong monster they control.
One Day of Peace	Easily the best stall card in the game. The +1 for your opponent is offset compared to the results. No advantage lost when played. Can be used after you attack to take no damage for a turn. Sets up for big plays and OTKs. Works very well in Exodia/Final Countdown Decks. There is also an OTK/FTK loop with this card in Gishki Decks, where multiple copies of this and other draw cards were repeatedly recycled with Evigishki Mind Augus to Deck out the opponent in a single turn. Can be recycled and reused by Magician of Faith (which is Unlimited in the TCG). However, it does give the opponent an opportunity to establish a strong field instead.
One for One	Nice searcher. Formerly abused in Frog Burn FTK, Mind Master OTK, and Plant Synchro. Loss in card advantage is easily recoverable with the right setup. Will probably remain Limited due to Neptabyss, the Atlantean Prince and various combos hinging on other Level 1 monsters such as Level Eater, Jet Synchron, Raidraptor - Last Strix, D/D Lamia and D/D Savant Kepler.
Pantheism of the Monarchs	A superior Destiny Draw for Monarchs that thins the Deck while drawing out key cards and dumping cards such as The Prime Monarch. The player can also banish this card from the Graveyard afterwards to search another Monarch Spell/Trap card, even in the turn it was activated. Can also be searched with Tenacity of the Monarchs. This card also played a key role in Monarch Magical Explosion deep draw FTKs. This card is Unlimited in the OCG.
Pendulum Call	Sets up easy Pendulum Summons with Magician monsters while protecting the player's Pendulum Scales from cards such as Twin Twisters and Wavering Eyes. This card is Unlimited in the TCG.
Primal Seed	Can cause FTK loops when allowed in multiples, combined with Banisher of the Light or any similar card that banishes anything that would go to the Graveyard. With a Primal Seed banished, activate any burn card (even Sparks), then use a second Primal Seed to recover the first Primal Seed and your burn card. Repeat until your opponent is defeated. However, this setup is somewhat more convoluted than some other FTK loops. This card is Unlimited in the TCG.
Raigeki	Simply too powerful to be Unlimited. Since it destroys your opponent's monsters while leaving yours unscathed, it is much stronger than Dark Hole in most Decks. Lightning Vortex is a more fair version of this card.
Reasoning	Was used a lot by Turbo and OTK Decks. Free Monster or easily dumps other cards to Graveyard, both of which can be beneficial. This card saw heavy play in Infernoids, which can dump vast amounts of Infernoid monsters for future use, causing it to be re-Limited.
Reinforcement of the Army	Too broad. This card adds additional speed to many Decks, like Evilswarms, Lightsworns, Six Samurais, tellarknights, HEROs, Ninjas, Inzektors (grabs Dark Grepher or Armageddon Knight), and Infernities (for the same reason as Inzektors). Certain Warrior Decks have their own version of this card, which prevents this from going to 2 to assist other Warrior Decks.
Rekindling	Very powerful Spell Card. Can Special Summon as many FIRE monsters from your Graveyard with 200 DEF as possible. Powerful plays with it include reviving multiple copies of Laval monsters like Volcano Handmaiden, Magma Cannoneer, Lancelord, Forest Sprite (which can all be easily sent to the Graveyard via Molten Conduction Field) to easily Synchro Summon Shooting Quasar Dragon or Red Nova Dragon, Brotherhood of the Fire Fists Spirit and Leopard to Synchro Summon another Brotherhood of the Fire Fist - Horse Prince, Fire King monsters like Avatar Yaksha and Avatar Barong to make easy Rank 4 Xyz Summons, and Infernoid Decatron, to dump multiple Infernoids in the GY while enabling Link Summons, allowing further branching plays. This card is Unlimited in the OCG.
Royal Tribute	Particularly disruptive when used on the first turn, leaving one vulnerable and unable to retrieve what has been lost because of Necrovalley. You also see their hand by default. This card is Unlimited in the OCG.
Scapegoat	Originally placed on the list as it was an effective stall tool in the early competitive game, but the rise of widespread piercing damage limited that utility. Was part of the Goat Control Deck, but now Metamorphosis has been forbidden. Allows for easy Synchro Summons and especially Link Summons, where it can produce a Firewall Dragon (Forbidden) from just 1 card. This card is Semi-Limited in the OCG.
Set Rotation	Likely hit due to a loophole involving Field Spells such as "Gateway to Chaos" and "Oracle of Zefra", whose archetype-locked search-on-activation effecs are mandatory, therefore preventing their activation in the very likely case the opponent has nothing to search. This means it secures your Field Spell AND locks your opponent's for free, with the only way out for them being using backrow self-removal, which can be a hard hit to recover for some Decks whose Field Spells are vital in getting them going.
Sky Striker Mecha - Hornet Drones	An easy, instant 1-card Sky Striker Ace Link Monster, which does not use the Normal Summon. Highly splashable, and searchable by Engage and recoverable by Kagari. Key card in Link Decks, both those that use Sky Strikers and those looking to set up a Knightmare lockdown.
Slash Draw	Limited after the rise of FTK strategies that stack the Deck, using cards such as Dr. Frankenderp, to ensure its effect will go off, nuking the field and causing deadly burn by itself. This card is Unlimited in the OCG.
SPYRAL Resort	Key card in SPYRALs. Protects SPYRALs from the opponent's card effects, and searches every turn. If going second, this enables easy OTKs. Its maintenance cost of shuffling cards back into the Deck just lets them be searched again, so is effectively not a cost.
Symbol of Heritage	Can revive any monster if you have 3 or more copies of that monster in your GY. Can cause loops with cards like Dewloren, Tiger King of the Ice Barrier (Which is Semi-Limited in the OCG and Limited in the TCG), Ancient Fairy Dragon (Forbidden in the OCG), and can be reused with cards like Mist Valley Falcon. Searchable by Hidden Armory and Power Tool Dragon. Even easier to abuse in Cyber Dragons, Harpies, and SPYRALs, since they have multiple monsters that treat themselves identically in the GY. Was probably Limited due to most Decks in the meta being fast enough now to reach 3 copies effortlessly, or because of Lonefire Blossom coming to 3.
Terraforming	Searches any Field Spell. It's especially useful to grab powerful Field Spells early in the game, such as Divine Wind of Mist Valley, Dragonic Diagram (Forbidden in the OCG), Chicken Game (Forbidden in the TCG), and Union Hangar, though it can become a dead draw otherwise. This card is Semi-Limited in the TCG.
Upstart Goblin	An inferior Pot of Greed that lets you draw 1 card, then has your opponent gain 1000 LP. Previously Limited due to use in Makyura Exodia Decks until Makyura was Forbidden, but later re-Limited again after heavy play in the TCG. 1000 LP is often worth the extra draw power in most Decks. This card is Unlimited in the OCG.
Imperial Order	Powerful Spell lock via a Continuous Effect, unlike others that start a chain. This card alone can shut down Decks. However, this card has now been errata'd so that the 700 LP cost occurs during both player's Standby Phases, and it is mandatory, preventing you from turning it off at will during your own Standby Phase.
Macro Cosmos	Same as Dimensional Fissure. Gives an almost automatic win against another player if they run a Graveyard-reliant Deck and you don't. This card is Unlimited in the OCG.
Metaverse	Activates a Field Spell directly from the Deck. Grants the user the ability to activate problematic Field Spells like Magical Mid-Breaker Field or Mystic Mine on their opponent's turn after having set up their own combo, adversely affecting their opponent's strategy. This card is Unlimited in the TCG.
Skill Drain	One card to continuously stop a large number of cards. Works well with cards such as Beast King Barbaros and Decks like Qli, Dark World and Yang Zing. See also: Skill Drain Deck. This card is Unlimited in the OCG.
Solemn Judgment	Can negate almost anything, having a cost you can always pay. This card is Unlimited in the OCG.
Solemn Warning	A lot of effects that Special Summon are present in the game. Paying 2000 LP to use this card is almost always worth breaking a loop that would otherwise generate several large monsters. Even though Bottomless Trap Hole is arguably more powerful with Ignition Priority being revoked, this card can still counter loops and hits monsters which Bottomless cannot hit. This card is Unlimited in the OCG.
Soul Drain	Many Decks rely on Graveyard and banished effects in the current meta. This card could easily defeat an entire Deck, especially Dark World Decks. This card is Unlimited in the OCG.
Trickstar Reincarnation	Hit to stop a hand loop which created OTK/FTKs. Banishes the opponent's hand instead of discarding, making the retrival of said cards much harder. No limit on the number of times you can activate both effects. This card is Unlimited in the TCG.
True King's Return	Easily searched by Dinomight Knight, the True Dracofighter (also Limited in the TCG), and generates easy advantage during either player's turn. This card is Unlimited in the OCG.
Wall of Revealing Light	Facing three in an Exodia Deck with LP recovery would be a real pain, especially because of Hope for Escape. Combos well with Reversal Quiz. Also abusable with Last Turn and Self-Destruct Button, both of which are Forbidden. This card is Unlimited in the OCG.
Semi-Limited
ABC-Dragon Buster	Boss "A-to-Z" Monster Summonable if its materials are on the field or in the Graveyard, which is relatively easy to achieve with cards like Ties of the Brethren and Future Fusion. Can banish a card during either player's turn, allowing easy disruption during your opponent's turn and clearing the way for OTKs. It can also escape destruction with its second effect during the opponent's turn, restoring its materials for the next turn to Summon a fresh ABC-Dragon Buster and/or make Rank 4 Xyz Summons. Far outclasses other "A-to-Z" monsters, whose materials must be banished from the field, cannot be Special Summoned from the Graveyard, use Ignition Effects that aren't chainable (excluding A-to-Z-Dragon Buster Cannon), and can only destroy cards (excluding VWXYZ-Dragon Catapult Cannon). This card is Unlimited in the TCG.
Ash Blossom & Joyous Spring	handtrap that can fit into most Decks. Can negate any effect that affects the Deck, disrupting most plays in the current game and blocking combos key to the function of the Deck, which can turn a Duel one-sided. This card is Unlimited in the TCG.
Destiny HERO - Malicious	Pulls another copy of itself directly from the Deck if it's in the Graveyard. No once per turn restriction. Can be used for easy Synchro and Link Summon plays. This at 3, combined with Armageddon Knight (Limited in the TCG), is an easy Link-3 Link Monster. This card is Unlimited in the OCG.
Dinowrestler Pankratops	Easily Special Summons itself to the field when your opponent has more monsters out. Easy Special Summon = easy Link Material. Also offers on-the-spot Quick Effect destruction by Tributing another Dinowrestler, which can include itself. This card is Unlimited in the TCG.
T.G. Hyper Librarian	Super splashable, low Level with decent ATK, good effect that works when either player Synchro Summons. Can be broken when comboed with Formula Synchron. This card is Unlimited in the TCG.
Trickstar Candina	Searches Trickstar Reincarnation on its Normal Summon, which is bad enough in itself. When left out, it seriously limits your opponent's options, as they could be put into kill range by any Spell/Trap they activate. This card is Unlimited in the TCG.
Fossil Dig	Searches a large number of Dinosaur monsters, such as "Babycerasaurus", "Miscellaneousaurus" (which can be used as a handtrap), "Petiteranodon" (both it and "Babycerasaurus" can be destroyed in the hand by the effect of "True King Lithosagym, the Disaster" {Foridden in the TCG} for easy advantage), and "Souleating Oviraptor", which can search any Dinosaurs this card cannot. This card is Unlimited in the TCG.
Limiter Removal	Creates easy OTKs in Machine Decks. Most of the time your monsters won't be destroyed during the End Phase because you can just Synchro/Xyz/Link Summon with them. This card is Unlimited in the TCG.
Mystic Mine	A Field Spell (easily searched) that causes easy lockdowns. Monster effects are vital in the current game, so being locked out of them is devastating. Can cripple your opponent if you control no monsters, and the only counters your opponent has are either to remove it (harder to get to removal if monster effects re out of the question) or to control no monsters (which leaves them a sitting duck to be OTK'd next turn). This card is Unlimited in the TCG.
Nekroz Cycle	Key Ritual Spell in Nekroz Decks. In addition to being able to Ritual Summon any Nekroz Ritual Monster from your Graveyard (allowing easy use of both of their effects) as well as your hand, it can also banish itself and 1 Nekroz monster from your Graveyard to add 1 more Nekroz Spell Card from your Deck to your hand if you control no monsters. This card is Unlimited in the TCG.
Sky Striker Mecha - Widow Anchor	Generic Spell which, in the right Decks, can remove an effect that's troubling you and act as a Change of Heart, giving you a free Link Material. This card is Unlimited in the TCG.
Sky Striker Mobilize - Engage!	If you have enough Spells in your Graveyard, it's a +1. Searches Hornet Drones (Limited) and Widow Anchor (also Semi-Limited in the OCG). This card is Unlimited in the TCG.
Super Polymerization	Powerful, chainable Quick-Play Spell Card that cannot be chained to. Can fuse monsters from either player's side of the field. Mainly abused in HEROes (to Fusion Summon Absolute Zero, Nova Master, Gaia, Great Tornado, The Shining, and Escuridao), Zombies (for Dragonecro Nethersoul Dragon while Zombie World is on the field), and Shaddolls (For El Shaddolls Construct (Forbidden in the TCG), Winda, Grysta, Shekhinaga, Wendigo, and Anomalilith). Can also be used to fuse any two Synchro or Xyz Monsters from either side of the field to make Elder Entity Norden (Forbidden). Strong when used in Predaplants, whose effects can easily make any monster your opponent controls an eligible material. Also viable in Invoked.
Personal Spoofing	Once per turn, allows you to shuffle back an Altergeist you don't need to gain one you do, which is usually Altergeist Multifaker (Limited in the OCG). Unbricks most Altergeist hands. Not a hard once-per-turn, so can be used in multiples for even more searching power. This card is Unlimited in the TCG.
Solemn Strike	Powerful Counter Trap Card that can negate any Special Summon or monster effect for only 1500 LP. Can be somewhat better than Solemn Warning (Limited) due to its lower cost and somewhat broader negation pool, and can be searched by cards such as Guiding Ariadne. This card is Unlimited in the TCG.
No longer on list
A-Assault Core	Superb card in ABCs, and can also work in other Decks that use LIGHT Machines, like Cyber Dragons. Can be equipped directly from the Deck with Union Hangar. Can be used to give immunity to powerful monsters like ABC-Dragon Buster. Returns another Union monster from your Graveyard to your hand when it leaves the field, including when used as a material, and including other copies of itself, resulting in a loop when combined with Firewall Dragon (Forbidden) and Cannon Soldier (Forbidden in the OCG) that allowed for an OTK. Removed from the TCG list after Firewall Dragon's Forbidding.
Abyss Soldier	Semi-Limited from April '05 to Sept '05 due to its abuse with Sinister Serpent, allowing free bouncing, once per turn. After Sinister Serpent got Forbidden, this came off the list.
Aleister the Invoker	Easily searched by Magical Meltdown (which is searchable by Terraforming, Limited in the OCG), and searches Invocation upon its Summon, which can Fusion Summon an "Invoked" Fusion Monster by using this card and monsters in either player's Graveyard. When used in combination with the Windwitch engine (see Windwitch - Ice Bell), this can result in a minimum field of Crystal Wing Synchro Dragon and Invoked Raidjin, and has high versatility given the range of Invoked Fusion Monsters.
Apprentice Magician	Was used to get Magician of Faith from your Deck face-down to get access to its effect. Nephthys Decks also used it to search Hand of Nephthys to quickly Summon Sacred Phoenix of Nephthys. The Apprentice Magician > Old Vindictive Magician Monarch combo didn't really contribute to its initial Semi-Limitation, so it came off the list. Also, Flip Effect monsters are considered to be too slow nowadays.
Apoqliphort Towers	Powerful boss monster in Qlis. Could easily be Tribute Summoned when released due to the initial swarming capabilities of the archetype. While in the OCG the ubiquity of Utopia the Lightning prevented this from becoming enough of a threat to be Forbidden, a lot of Decks in the TCG were incapable of removing this card due to its immunity to most effects and it reducing the ATK of Special Summoned monsters by 500, forcing them to run specific counter cards like Heroic Champion - Excalibur. However, it could easily be dealt with after the release of more generic counter cards such as Crystal Wing Synchro Dragon and Kaijus. Now not nearly as powerful due to New Master Rules making harder to gather enough Tributes, but can still be a force to be reckoned with, especially if you lock out the Extra Deck with cards like Domain of the True Monarchs.
Archlord Kristya	Strong ATK, seals Special Summons, and is difficult to get rid of since it goes back to the top of the Deck instead of the Graveyard. Generates a +1 when Special Summoned. Came off due to lack of use in the current meta.
Artifact Moralltach	Can destroy any face-up card your opponent controls without targeting when it's Summoned. Can be searched with Artifact Sanctum and Artifact Ignition. Can be reused with Artifact Failnaught or Call of the Haunted.
Atlantean Dragoons	Amazing Searcher. Adds any Sea Serpent from your Deck to your hand when sent to the Graveyard as a cost for a WATER monster's effect. Key card in Mermail Decks. Also allows other Sea Serpents to attack directly, therefore gaining Atlantean Marksman's effect. Can easily be searched with Atlantean Marksman, Genex Undine, and Summoner Monk.
Black Rose Dragon	Universal Nuke. See also: Debris-Hime Deck. Top Decks wouldn't really use more than one in their Extra Deck anyways.
Black Luster Soldier - Envoy of the Beginning	Can be Special Summoned easily, good effects, high ATK. Honest can be used on its first attack, then the 2nd attack would be deadly. Basically a better Chaos Sorcerer (below).
Blackwing - Gale the Whirlwind	Can be Special Summoned in Blackwing Decks very easily. A reusable permanent Shrink. Universal Tuner. However, Blackwings haven't done much in a long time, so it was brought down to 3.
Blackwing - Kalut the Moon Shadow	Can easily turn battles around in Blackwing Decks. Unlike Honest, it can even be used when attacking directly for massive damage. Blackwings aren't as good as they once were so this came back to 3.
Breaker the Magical Warrior	Back when it was Forbidden/Limited, +1 cards were overpowered; Breaker lets you destroy a card almost for free and you'll still have a monster, or you could leave it as a 1900 Beatstick which was quite a lot at the time.
Brionac, Dragon of the Ice Barrier	Was formerly Forbidden due to a lack of a once per turn restriction, allowing you to bounce cards with its effect multiple times per turn and reuse your own cards for loops and OTKs. Now, it has been errata'd so it can only be used once per turn, and can only bounce your opponent's cards, not your own.
Brotherhood of the Fire Fist - Rooster	Key card in Fire Fists. Adds any Fire Fist monster from your Deck to your hand when Summoned by a Fire Fist monster's effect. Can also search Fire Formation Spell/Trap cards. Can be searched easily with Brotherhood of the Fire Fist - Horse Prince or Fire Formation - Tenki. Can be reused with Brotherhood of the Fire Fist - Spirit or Brotherhood of the Fire Fist - Lion Emperor. Fire Fists aren't relevant anymore though, so it went back to 3.
Brotherhood of the Fire Fist - Spirit	Key card in Fire Fist 3-Axis Deck. Works well with Brotherhood of the Fire Fist - Rooster and Brotherhood of the Fire Fist - Leopard. Searchable via Fire Formation - Tenki and/or Rooster. At 3, easily makes a new Brotherhood of the Fire Fist - Horse Prince every turn. Also reusable via Rekindling and Crane Crane, and can be returned to your hand via Brotherhood of the Fire Fist - Lion Emperor to start the combo all over again. Fire Fists aren't relevant anymore though, so it went back to 3.
Burner, Dragon Ruler of Sparks	Were formerly Forbidden due to being able to easily special Summon their respective Level 7 Dragon Rulers directly from the Deck for easy Rank 7 Xyz Summons and/or Level 8 Synchro Summons. Now that their respective Level 7 counterparts are Forbidden in both the TCG and OCG, these cards came back to 3.
Lightning, Dragon Ruler of Drafts
Reactan, Dragon Ruler of Pebbles
Stream, Dragon Ruler of Droplets
Card Trooper	Can be a good beatstick for 1 turn. Sets up the Graveyard for many Decks. When it dies, you draw 1, so no advantage lost. Can be doubled up with Machine Duplication.
Chaos Sorcerer	Can be Special Summoned easily, decent effect. However, relatively low ATK. With the rise of Chaos Decks, getting this out is even easier than before. Searchable with Justice of Prophecy. Came off the list due to its lack of use in the meta, and Black Luster Soldier - Envoy of the Beginning is considered better anyways.
Chronomaly Nebra Disk	Adds any Chronomaly card from your Deck to your hand other than itself when Normal Summoned, mainly Chronomaly Crystal Skull (who then searches another copy of this card), and Chronomaly Golden Jet, who can be used to make easy Rank 5 Xyz Summons with this card or with Artifact monsters. Has decent ATK. Can also revive itself from the Graveyard for Rank 4 (or 5 with Golden Jet) Xyz Summons if you only control Chronomaly monsters. Mainly hit due to Chronomaly/Artifact builds topping in the OCG before The Duelist Advent.
Coach Soldier Wolfbark	Key card in 4-axis Fire Fist Decks. Special Summons Level 4 Fire Fist or Fire King monsters from your Graveyard for easy Rank 4 Xyz Summons. At 3, can easily make a new Brotherhood of the Fire Fist - Tiger King each turn. Can be searched easily with Fire Formation - Tenki. Came off the TCG list due to the lack of Fire Fist and Fire King Decks topping.
Constellar Ptolemy M7	Good effect. Can be used in Hieratics, Dragunitys, Constellars, or any Deck that makes easy Rank 6 monsters. Automatically usable after one of your other Constellar Xyz Monsters runs out of Materials. Key card for the Evigishki Gustkraken hand loop, which is not relevant anymore.
Cyber Dragon	Can be Special Summoned easily. Good ATK. Usable in many Decks. However, there are increasing numbers of newer monsters with effects similar to this card, and increasing amounts of newer Decks that can Special Summon "a bunch of monsters in one turn", so older Decks need this. Also, the opponent can use Chimeratech Fortress Dragon against you if you're using machines as well (e.g. Morphtronics, Salvo, Gadgets).
D.D. Assailant	Hit back when Warrior Toolbox Decks were Tier 1. Powerful in a different way to its similar counterparts D.D. Warrior and D.D. Warrior Lady, as it needs to be destroyed to fire off its banishment effect, meaning it can attack low-power monsters without wasting its effect. The Warrior Toolbox is irrelevant now, so this is gone from the list.
D/D Lamia	A reusable Level 1 Tuner that can revive itself for Synchro plays by sending any D/D or Dark Contract card from your hand or field to the Graveyard.
D/D Swirl Slime	A polymerization on legs that can Fusion Summon a D/D/D Fusion Monster using D/D monsters from your hand as materials, including itself. It can also banish itself from the Graveyard afterwards to special Summon a D/D monster from your hand.
D.D. Warrior Lady	Similar to D.D. Assailant, but this card had the option to remove the monster, or not to remove the monster. Ultimately, the lack of need to be destroyed by battle to use its banishment effect would mean this came off the list a while after Assailant.
Dante, Traveler of the Burning Abyss	A generic Rank 3 Xyz Monster that can easily fill the Graveyard with monsters, such as Burning Abyss and Phantom Knights monsters for easy advantage. Can replace or even recycle another copy of itself once it is sent to the Graveyard through any means, and can also be used to easily Xyz Summon Beatrice, Lady of the Eternal (Limited in the TCG). It also forms a small loop with Cir, Malebranche of the Burning Abyss (Limited in the TCG).
Dark Magician of Chaos	It's a strong monster with a very good effect; its effect even works when it's Special Summoned, making it more powerful than Magician of Faith, who is also Unlimited. Dark Armed Return Decks were godly with this card. However, this card was errata'd so that it can only retrieve one Spell per turn, during the end phase of when it's Normal or Special Summoned, allowing it to come off the list.
Dark Scorpion - Chick the Yellow	Capable of bouncing your own card back to the hand. Was capable of forming an OTK with Makyura the Destructor and Call of the Haunted where, whilst under Makyura's effect, you would revive this card with Call of the Haunted, damage your opponent, bounce Call of the Haunted, destroy this card, and repeat. Makyura is Forbidden now, and this card has little use otherwise.
Dark Strike Fighter	Was formerly Forbidden due to being able to tribute any number of monsters on your field during either of your main phases to create easy OTKs, and a minimum of 4000 damage by itself in some cases. Now, they changed the effect so Dark Strike Fighter can only tribute one monster per turn during your Main Phase 1.
Debris Dragon	Highly usable with the number of Level 3 monsters with very low ATK like Lonefire Blossom, Dandylion, Card Trooper, etc. Can easily make LEVEL 7 Synchros like Black Rose Dragon, or higher-Level monsters like Trishula if Tokens are present on the field. Could also be abused in Dragon Ruler Decks (where it was searchable via Tempest) to Synchro Summon Star Eater or to bring back Flamvell Guard or The White Stone of Legend for Level 8 Synchro Summons in Dragon Ruler Decks. However, it does require a player's Normal Summon, making it far slower, and hard to reuse.
Demise, King of Armageddon	See Demise/Doom OTK. The eventual lack of such Decks in the meta resulted in this card coming off the list.
Destiny HERO - Disk Commander	Its effect as originally printed had no restriction, which proved to be far too powerful. Several cards could revive it, and they were effectively turned into Pot of Greeds by Disk Commander's effect. It now has a new errata as of 2018, which limits the effect to once per Duel and means it can't be Special Summoned from the Graveyard in the same turn it's placed there, so is much less useful.
El Shaddoll Winda	Key Fusion Monster in Shaddoll Decks along with El Shaddoll Construct (above). Restricts both players to 1 special Summon per turn and can't be destroyed by the opponent's card effects. Can be Fusion Summoned easily with Shaddoll Fusion, Nepheshaddoll Fusion or El Shaddoll Fusion, all of which can also be recycled with this card's effect. However, it isn't particularly needed on the list if Construct is considered powerful enough to be Forbidden, which it isn't (in the OCG) anymore anyway.
Elemental HERO Bubbleman	Mainly was Limited due to making combos and causing OTKs with Elemental HERO Stratos (Who is Forbidden in the TCG). Can easily make Rank 4 Xyz Summons or Fusion Summons with Miracle Fusion or Mask Change. Second effect can turn around games, but is rarely pulled off nowadays.
Evilswarm Exciton Knight	Generic Rank 4 Xyz Monster with a powerful destruction effect. Can nuke the field whenever you have less cards than your opponent, and the effect can even be chained to cards like Bottomless Trap Hole, Compulsory Evacuation Device, Torrential Tribute, etc. While it has low ATK and makes your opponent take no more damage that turn, the loss in card advantage when hit by this card's effect can potentially be devastating against some Decks, such as Pendulum-based Decks.
Evilswarm Ophion	Very powerful Rank 4 Xyz with high ATK. Can be Summoned very easily in Lswarm Decks with Evilswarm Castor, Evilswarm Kerykeion, Evilswarm Mandrago, and Rescue Rabbit. Seals special Summons of Level 5 or higher monsters, and can add any Infestation Spell/Trap card from the Deck to the hand, mainly Infestation Pandemic and Infestation Infection.
Exiled Force	Key to the Warrior Toolbox Deck which was once topping. This represented 1-for-1 monster removal, a rare sight in the early competitive scene.
Formula Synchron	Easily Summoned with cards like Glow-Up Bulb and Tokens made by Dandylion. An instant +1. Crazy when comboed with T.G. Hyper Librarian, who is Limited in the OCG. Can even be used for a Synchro Summon during the opponent's turn.
Gladiator Beast Bestiari	Required to Summon Gladiator Beast Gyzarus, and as a key means of S/T removal. However, Gladiator Beasts haven't done much in a long time, so it came down to 3.
Goblin Zombie	Very good searcher. In a Zombie Deck, it can be more abusable than Sangan or Witch of the Black Forest because of their revival power. Not many people would use 3 anyways and zombie Decks aren't topping anymore.
Gorz the Emissary of Darkness	Stops OTKs AND Special Summons a good Token. Turns games around with no real effort.
Goyo Guardian	Very high ATK for a Level 6 Synchro Monster. Good effect. Summons the opponent's monster right away so it can be used for Synchro/Xyz Summons. Now it has an erratum that now makes it only Summonable by EARTH Tuner monsters. Even prior to that, its effect was eventually considered too slow to pull off in the current meta; plus the three successive formats following it (Xyz, Pendulum, and Link) weren't as exploitable by its effect, and in the case of the latter two, impossible; so it was inevitably going to come off anyway.
Grandsoil the Elemental Lord	Uniquely among "Elemental Lord" cards, its activated effect was originally not a hard once-per-turn, which allowed for infinite loops. For example: with the proper setup, Firewall Dragon (now Forbidden) could return this card to the hand, then be used to Special Summon another Firewall Dragon. This card can then Special Summon itself, and revive the spent Firewall Dragon, which also resets its bounce effect. It could also be looped with cards such as Dewloren, Tiger King of the Ice Barrier (Limited) and Mist Valley Shaman. This card has since been errata'd to add this restriction.
Green Baboon, Defender of the Forest	Before, it could be Special Summoned when a Beast was destroyed by battle or by a card effect. This was rather good with a relatively low cost for high ATK. Now they changed the ruling and it can't be used during the Damage Step, so destroying by battle won't Trigger its effect.
Green Gadget	Gadget Decks used to top frequently, but aren't as powerful as they once were. Most Gadget Decks wouldn't run more than 2 of each anyways.
Red Gadget
Yellow Gadget
Honest	Amazing effect. Allows your monster to run over any other monster, and deal decent damage. Easily reused with Beckoning Light. Abusable with BLS.
Ignis Heat, the True Dracowarrior	Allows easy searching and/or activation of True Draco and True King Continuous Spells directly from the Deck, though this is less devastating than Dinomight Knight, the True Dracofighter as the effects of the Continuous Spells can only be activated during the player's turn. Removed from the List due to Master Peace, the True Dracoslaying King being Forbidden.
Injection Fairy Lily	She was considered to be too fast and too strong for the format at the time. Now there are Decks other than beatdown types, so this came off.
Inzektor Hornet	A solid one-for-one destruction card with perks. The key to Inzektors. Easy to dump into the Graveyard with Foolish Burial, Armageddon Knight, or Dark Grepher (all now Limited in the TCG). Was primarily used to perform loops. Inzektors have since faded into irrelevance, though, and this card stayed on the list much longer than it should have according to some players.
Jinzo	Very popular early in the game's history since back then the game was slow enough to allow for monsters to be Tribute Summoned. Then the metagame picked up speed, where Special Summons became more favourable, and Jinzo dwindled in popularity due to both Royal Decree and presence of better monsters to Special Summon, so it came off the list. Naturia Bamboo Shoot is also a Tribute monster, but it also stops Spells and not just Traps, although it is less splashable.
Judgment Dragon	Can be Special Summoned easily in Lightsworns. Low cost to nuke the Field except itself. 3000 ATK. Double JD is broken, especially when they can be returned to your hand with Beckoning Light. However, in the OCG with the new Priority ruling change, the increase of anti-Special Summon cards for high Level/LIGHT (chaos) monsters, and Lightsworns not topping much might have been the reason to unlimit this.
Kozmo Dark Destroyer	The boss monster of Kozmo Decks. Can target and destroy any monster on the field when it's Summoned. While ordinarily not something worth writing home about, when paired with the lower level Kozmo monsters, it essentially becomes a form of pseudo-disruption during your opponent's turn. Quite hard to remove due to its high ATK and invulnerability to targeting effects. Also Special Summons another Kozmo monster from the Deck when it dies, and can even destroy itself to trigger this. Searchable by Kozmo Farmgirl and Kozmo Tincan, and reusable by Kozmotown and Kozmo Strawman.
Kuribandit	Splashable Level 3 monster with a good effect. Tributes itself to send the top 5 cards from your Deck to the Graveyard during the End Phase of turn it's Normal Summoned, while also retrieving 1 Spell/Trap among them (namely cards like Soul Charge, Foolish Burial, [[]], etc.) to your hand. This card is Unlimited in the TCG.
Legendary Six Samurai - Shi En	Stops 1 Spell or Trap every turn. Very easily Summoned in Six Samurai. Can prevent himself from being destroyed if there's another Six Sam out. Came off the list due to the lack of Six Samurai in the meta, and the increasing prevalence of activatable Spell/Trap effects.
Light and Darkness Dragon	See Perfect Circle. Not as abusable now that Tribute Summoning is considered slow.
Lumina, Lightsworn Summoner	Easy effect that special Summons a Lightsworn monster from the Graveyard. Gives uses to cards that are useless in the hand (e.g. Wulf, Lightsworn Beast). Nice mill effect. Since Lightsworns aren't topping anymore, this came off the list.
Magician of Faith	Allows the player to reuse Spells Cards, mostly ones with broken effects like Harpie's Feather Duster (Forbidden in the TCG and Limited in the OCG), Dark Hole and Soul Charge (Limited). Was part of the Goat Control and Tsukuyomi Lockdown Decks. Came off the list due to being too slow for the current metagame.
Manju of the Ten Thousand Hands	Adds any Ritual Spell or monster to your hand when Normal or flip Summoned. Mainly hit due to abuse in the Nekroz archetype in the OCG.
Manticore of Darkness	There is an OTK with this card (but it's too inconsistent with the current format), and it worked well with Card of Safe Return (now Forbidden).
Marauding Captain	Another important part of the Warrior Toolbox Deck. Special Summons another low-level monster when it's Normal Summoned, including Exiled Force, D.D. Warrior Lady, or another copy of itself, and you can prevent your opponent from attacking at all without any monster removal if you get 2 out.
Marshmallon	Relatively hard to kill. Instantly inflicts 1000 damage, which is quite a lot. However, Spirit Reaper went back to 3, so it was inevitable that this would also go back to 3 due to the high quantity of removal power.
Mask of Darkness	Well, Royal Oppression (now Forbidden) became Limited when this became Unlimited, not that anyone was using this card anyway. Used to be part of the Tsukuyomi Lockdown, but isn't anymore with Time Seal now Forbidden.
Mermail Abyssgunde	Key card in Mermail Decks. Special Summons any Mermail from your Graveyard when discarded to the Graveyard. Good monsters it can revive include Mermail Abysspike, Mermail Abysslinde, Mermail Abyssdine, Mermail Abyssmegalo, Mermail Abyssteus, or Mermail Abyssleed for easy combos and Xyz Summons. Can be searched by Mermail Abyssteus (below) and reused with Salvage or Mermail Abyssturge. Came off the TCG list due to the lack of Mermails in the current meta.
Mermail Abyssteus	Key card in Mermail Decks. Can be Special Summoned easily. Adds any Level 4 or lower Mermail monster from your Deck to your hand when Summoned by its effect. Can be searched easily with Abyss-sphere and reused with Abyss-squall or Mermail Abyssgunde (above).
Mezuki	Creates +1 Summons. Effect is easy to pull off and reuse. Staple in almost any Zombie Deck to generate loops and OTKs. Easily searchable with Foolish Burial or Lavalval Chain, and reusable with Burial from a Different Dimension. Was Unlimited since Zombies are no longer as good as they once were.
Miscellaneousaurus	Can allow Dinosaurs to operate without fear during the Main Phase, and can also search out a vast array of useful Dinosaurs. The downside to its second effect can be worked around with cards like Babycerasaurus and Petiteranodon to cut down its banishment requirements. An instant Level 5 Synchro or Link-2 when combined with Souleating Oviraptor and Jurrac Aeolo.
Necro Gardna	Easily used in Lightsworns, and reused with Burial from a Different Dimension (however, this is Limited). Lightsworns have not been topping lately due to their relative inconsistency, so this was Unlimited to give them a chance in the current meta.
Nekroz of Brionac	Key card in Nekroz. Simply by discarding itself, it can search effectively ANY Nekroz card (including Spells, thanks to Nekroz of Clausolas). Can also be Summoned to return up to 2 monsters Special Summoned from the Extra Deck back to the Deck, easily clearing the field. Nekroz have fallen into irrelevance, so it came back at 3.
Neo-Spacian Grand Mole	Can create locks, especially with Kaiser Colosseum (Forbidden in the TCG). Easily takes out boss monsters, particularly those with specialized Summoning requirements, and does not destroy or target. However, it needs to battle to use its effect, and is not used that often now anyway.
Number 11: Big Eye	Very powerful Rank 7 Xyz Monster. Good effect. Can permanently take any opponent's monster, with no restriction about how it can be used, although it can't attack the turn it uses its effect. Came back to 3 since the main Decks that Summoned this so easily (Dragon Rulers and Mermails) are dead and irrelevant, respectively.
Performapal Pendulum Sorcerer	This card played a pivotal role in Performapal Pendulum Decks, as it could search out key Performapal cards while triggering the effects of monsters such as Performage Plushfire and Guiding Ariadne. It could also be used to Summon Performage Trapeze Magician, leading to easy OTKs.
Phantom of Chaos	Was formerly abused in Sky Scourge Norleras Decks. Once those Decks stopped doing well, this was allowed to go back to 3.
Plaguespreader Zombie	Universal reusable Tuner. Its downside can be overridden by playing a search card afterwards, thus shuffling your Deck. Was taken off the list due to zombie/Synchro Decks that used this not topping anymore.
Protector of the Sanctuary	Formerly abused with things like Time Seal and Yata-Garasu as an additional layer of insurance for such a lock since the opponent could only break the lock by drawing with a card effect. Time Seal and Yata-Garasu soon got Forbidden, leaving no reason to limit Protector of the Sanctuary.
Raiza the Storm Monarch	Raiza was overused in Monarch Decks, and that was Tier 1 back then. Caius was released, along with other faster Decks so this was let off. Caius is now considered to be better anyways.
Reborn Tengu	Replaces itself when it leaves the field. Doesn't care about being Banished or Bounced, though it does when Spinned or used as Xyz Material. Abusable in Synchro/Link Decks. A similar case to Destiny HERO - Malicious.
Reflect Bounder	At the time they Limited this, Chaos Decks were Tier 1. The Envoys were also Forbidden at this time, but they realized that this didn't really need to be hit as hitting the Envoys was enough, so this later this came off.
Rescue Cat	Instant +1. Abusable by Gladiator Beasts, Naturias, Wind-Ups, Flamvells, Fableds, Madolches, Raccoons, and especially X-Sabers. Formerly Forbidden due to not having a once per turn restriction for its effect and not negating the effects of the Summoned monsters, allowing for easy OTKs with cards such as Uniflora, Mystical Beast of the Forest. Now, it can only be used once per turn and it negates the effects of the Summoned monsters. Can easily be searched with Summoner Monk.
Rescue Rabbit	Super splashable in many Decks. Fire Fists, Evilswarms, Gem-Knights, Gladiator Beasts, and more all can use this for instant Rank 4 Xyz or Fusion Summons. Key card of Dino Rabbit Decks.
Sacred Phoenix of Nephthys	At the time when it was Limited, destruction effects were the metagame, especially with Gadget Decks using it to the fullest extent possible. Nephthys could come back persistently, destroying backrow at the same time. Then the metagame picked up speed with both chainable Traps and Banishment Decks becoming more popular and widespread. Since then, Nephthys' usefulness has died down considerably, and is really only seen nowadays splashed in with Fire Kings.
Sangan	Universal searcher. Easily searched by Tour Guide From the Underworld and reused by Crane Crane. Adds a ton of consistency. Now it can only search once per turn, and prevents you from using the effects of the added card that turn.
Scarm, Malebranche of the Burning Abyss	Key searcher in Burning Abyss Decks. Searches any Level 3 DARK Fiend monster during the end phase of when it's sent to the Graveyard, mainly another Burning Abyss monster or Tour Guide from the Underworld (Limited).
Senju of the Thousand Hands	Same as Manju of the Ten Thousand Hands (above).
Sinister Serpent	Free discard for costs, etc. Turns discarding into a +0. Really annoying to be against with The Dark Door. Can be sent from your Deck to the Graveyard through Foolish Burial (Limited). Now, it'll Banish itself from your Graveyard at the end of your opponent's turn if it's still there by then, unless cards like Imperial Iron Wall and Chaos Hunter are active.
Snipe Hunter	Formerly abused in Gadget Decks due to massive hand advantage to fuel its effect. The lack of Gadget Decks around resulted in it coming off the list.
Spirit Reaper	Can't be destroyed by battle, but unlike Marshmallon, it destroys itself the moment it is Targeted. Its other effect is great, except against Dark World, which is not relevant. Came of the list due to its lack of use in the meta.
Spore	Related to Glow-Up Bulb, who is also Unlimited. Universal Tuner. Very potent Level altering effect. It is currently unknown why this card didn't go to Unlimited in the September 2012 format (its effect can only be used once per Duel, so no one ran more than one).
Star Seraph Sovereign	Key card in the Seraph engine. Allows for easy combos, pluses, and Rank 4 Xyz Summons when used in combination with other Seraph cards or tellarknights.
Summoner Monk	Great searcher. Was originally hit because it could grab Rescue Cat, who is now also Limited due to its errata. Combos well with Sacred Crane, as well as Shaddolls, Tellarknights, Star Seraphs and Elemental HERO's Shadow Mist or Stratos. Easy Rank 4 Xyz Monster/Level 8 Synchro Monster.
T.G. Striker	A Cyber Dragon-like Level 2 Tuner. Can start fast Synchro Summoning variety without using the Normal Summon. Came off the list due to its lack use in the Meta.
The Agent of Mystery - Earth	The Stratos equivalent for Agents. It's also a Tuner. Came off the list due to Agents not being relevant anymore.
Thousand-Eyes Restrict	Has a once powerful lockdown effect. Was part of the Goat Control Deck. Easily Fusion Summoned with Instant Fusion. Easily revived because of its low ATK and low Level (e.g. Graceful Revival and Limit Reverse). You can use Instant Fusion, use its effect, then Tribute it for a Monarch. However, this is rather slow for the current meta, so it came back to 3.
Thunder King Rai-Oh	Low Level, high ATK, seals search effects, and can negate a Built-in Special Summon. Great counter against most current Decks in the meta, which rely on both of the above. There are methods of getting around it, however.
Toadally Awesome	Strong Rank 2 Xyz Monster with many good effects. Can Special Summon a Frog monster from your Deck by detaching a material during either player's Standby Phase, can negate any opponent's card by sending an Aqua monster from your hand or field (even itself) to the Graveyard AND set that negated card to your field, and can recycle any WATER monster from your Graveyard (even itself) when it's sent to the Graveyard. Mainly hit due to Paleozoic Decks that were topping frequently due to this card in the OCG. Can also be splashed in some Rank 4 Decks that can Xyz Summon Bahamut Shark.
Tragoedia	Stops OTKs AND has other great effects. Can get very strong, can take opponent's monsters, or even alter its own Level for Synchro/Xyz shenanigans.
Treeborn Frog	Yes it's a free Tribute, but you can only activate 1 anyway. So, Limiting isn't going to do much. Semi-Limit is still OK because the new removal cards tend to remove 2 at once.
Tsukuyomi	Reusable Book of Moon effect. Was part of the Tsukuyomi Lockdown, but not anymore with Time Seal Forbidden. Not as good as it once was, so it came off the list.
Twin-Headed Behemoth	Monarch Decks used to run 3 at the time, keeping a monster to Tribute on the field whether it was destroyed by battle or by a card effect. Then a new ruling was made: "The effect of "Twin-Headed Behemoth" can only be used ONCE throughout the entirety of the Duel. Even if your Deck includes three copies of the card, between those three copies the effect can only be used once, not once each." This card became Unlimited after that ruling was released, and Monarchs then received Treeborn Frog (see above) and that replaced this card, even if the ruling wasn't made.
Vampire Lord	Was Limited for the same reasons as Sacred Phoenix of Nephthys above, being a strong card that just wouldn't go away in a time when effect destruction was the meta. Its effect could prove highly disruptive back when Graveyard effects were uncommon, but is now mediocre.
Wind-Up Magician	Summons a Wind-Up monster from the Deck whenever a Wind-Up Monster’s effect activates. The "Once while face-up on the field" restriction is easily overridden by Summoning another copy of itself and activating another effect afterwards. Crazy when comboed with Wind-Up Shark. Can be searched easily with Summoner Monk and Wind-Up Factory. Creates easy Xyz Summons. It can clog up your available Monster Zones when overused, though.
Wind-Up Shark	Can be special Summoned whenever another Wind-Up monster is Summoned. Can be searched easily by Summoner Monk and Wind-Up Factory. Works very well with Wind-Up Magician (Limited in the TCG). Creates easy Rank 3-5 Xyz Summons.
Windwitch - Ice Bell	Can Special Summon itself whenever you control no monsters, and can then Special Summon "Windwitch - Glass Bell" from your Deck (which can then search and Special Summon "Windwitch - Snow Bell"). Afterwards, you can Synchro Summon "Windwitch - Winter Bell" with this card and "Glass Bell", and then "Crystal Wing Synchro Dragon" with "Winter Bell" and "Snow Bell", which will be immune to destruction by card effects due to "Snow Bell".
Wisdom-Eye Magician	Key card in the Magician Pendulum engine. Can destroy itself to search ANY Magician Pendulum Monster in its place, while stashing itself away later for a Rank 4 Xyz or Odd-Eyes Fusion Summon. Can be searched easily with Pendulum Call or Performapal Skullcrobat Joker (also Limited) or Odd-Eyes Pendulum Dragon and easily reused with Nobledragon Magician.
Witch of the Black Forest	Much more powerful than its counterpart Sangan, since it's able to search out strong key monsters such as Dark Armed Dragon, Monarchs, Fire Fists, Hieratics, Bujins, Thunder King Rai-Oh, etc. AND most of the cards Sangan can search. Can be searched easily itself with Summoner Monk and some of the Prophecy/Spellbook cards. Dropped off the list due to an erratum that prevents you from using the effects of the added card that turn, similarly to Sangan.
Advanced Ritual Art	See Heralds combo and Demise/Doom OTK Decks. Not as broken as it used to be since the game got faster.
Allure of Darkness	The most splashable draw card since Pot of Greed. Its "downside" can be used for Graveyard setup.
Black Whirlwind	Gives major hand advantage to Blackwing Decks. However, Blackwings haven't been competitive in the meta in a long time, so it was brought back to 3.
Book of Taiyou	Formerly abused in Empty Jar Decks to force the activation of Cyber Jar, Morphing Jar, and Morphing Jar 2. All 3 are now Forbidden in the TCG, and aren't topping elsewhere, so this came up to 3.
Brain Control	Was formerly Forbidden due to being able to take control of any face-up monster your opponent controls for the small price of 800 LP. Now, it can only affect monsters that can be Normal Summoned/Set, which some Decks might never use.
Burial from a Different Dimension	Can reuse monsters like Mezuki, Plaguespreader Zombie, Necro Gardna, Blackwing - Vayu the Emblem of Honor, etc. Also allows a player to skip the delay on a Gold Sarcophagus search.
Called by the Grave	Easily activated during your turn to cancel out an opponent's handtrap (Maxx "C" Forbidden in the TCG, Ash Blossom & Joyous Spring, Semi-Limited in the OCG etc.). Potentially allows a player to build up near-impenetrable fields unopposed. Previously Semi-Limited to promote diversity.
Card of Demise	Lets you draw until you have 3 cards in your hand. While you can't Special Summon or inflict damage for the rest of the turn it's used, you can set a lot of Traps or activate Pendulum Scales, making it useful in stun Decks that use a lot of backrow. The latter drawback can also be circumvented by inflicting as much damage as possible before activating it.
Charge of the Light Brigade	It's like ROTA (Limited), but for Lightsworns. It also mills. Lightsworns became irrelevant enough for this to drop off the list.
Creature Swap	Formerly considered too strong for the meta back when there weren't as many removal cards. Also useless if the opponent uses evasion tactics to remove your ideal monster, or if said monster requires archetype specific resources to be useful.
Destiny Draw	Works very well with Destiny HERO - Malicious and is a godsend to Diamond Dude Turbo. Was a Semi-universal draw engine. Lack of relevant Destiny HERO monsters in general caused this card to come off the list.
Domain of the True Monarchs	A powerful Monarch support card that shuts down numerous Decks that rely on their Extra Deck. It also allows players to Summon powerful Tribute monsters such as Erebus the Underworld Monarch for only one Tribute.
Dragon Ravine	Can be used to search any Level 4 or lower Dragunity from your Deck to your hand OR act as a Foolish Burial to send any Dragon from your Deck to the Graveyard for easy Graveyard setup once per turn. Can be searched easily with Terraforming (Limited in the OCG) and Metaverse. Mainly Forbidden to try to kill Dragon Rulers, but with the Dragon Rulers now Forbidden themselves, it became Unlimited again.
Dragon Shrine	A Foolish Burial for Dragons (below). Additionally, if you sent a Normal Dragon to the Graveyard with this, you can send another Dragon-type monster to the Graveyard as well. Mainly hit to slow down Dragon Rulers in the OCG but with them now Forbidden, it was Unlimited.
E - Emergency Call	Searches ANY Elemental Hero, including Stratos (Limited in the TCG), who then searches something else. With ROTA at 1, A Hero Lives at 3, and Pot of Duality at 3, HEROs had way too much search power, and it allowed them to run ridiculously low monster counts.
El Shaddoll Fusion	Key Fusion Spell in Shaddoll Decks. As Quick-Play Spell you can activate it any time you want, including the Battle Phase to make easy OTKs. Shaddolls haven't been good in a while though, and its card advantage is often unfavorable when compared to Shaddoll Fusion.
Emergency Provisions	Formerly abused with Mirage of Nightmare, which is now Forbidden. Combos well with Good Goblin Housekeeping (also Unlimited) to draw several cards from your Deck at once.
Fire Formation - Tenki	Basically Reinforcement of the Army (Limited) for Beast-Warriors. Adds lots of speed to several Decks, like Constellars, Gladiator Beasts, Wind-Ups (for Wind-Up Rabbit), Bujins, Fire Kings, Koa'ki Meirus and especially Fire Fists, where it can search just about any Fire Fist monster from your Deck to your hand, and can be searched easily itself with most Fire Fist cards. Can also act as fuel for Fire Fist monster's effects and gives all beast-warriors 100 ATK. Initially Unlimited due to Fire Fists not being as good as they once were. Was put back on the OCG list again due to Zoodiac Decks topping, but the banning of Broadbull and Drident wiped Zoodiacs out, so now it is Unlimited again.
Fissure	A 'one for one' card that was rarely used outside of Gadget Decks, and faster Decks that could cope were made, so this came off.
Future Fusion	Allows for massive Graveyard setup, particularly using Machines, Dragons, Worms, Zombies, and Infernoids, where Chimeratech Overdragon, Five-Headed Dragon, Worm Zero, Dragonecro Nethersoul Dragon and Infernoid Tierra respectively can allow for a large number of monsters of the player's choice to be dumped. Both HEROs and Fluffals abuse this with Miracle Fusion and Frightfur Fusion, respectively. However, this card now has an erratum so that it must send the Fusion Materials during the Standby Phase after it is activated, making it slower and easier to remove.
Hieratic Seal of Convocation	Similar to E - Emergency Call, but with Hieratics. Opening with it pretty much meant you would OTK.
Instant Fusion	Instantly Fusion Summons any Level 5 or lower Fusion Monster from your extra Deck for easy Synchro or Xyz Summons. Mainly hit due to a two-card FTK involving this card and Elder Entity Norden but with Norden now Forbidden, this came off the list.
Level Limit - Area B	Excellent stalling device for no cost, effectively locking out most Decks that use lots of high-Level monsters. However, it does not affect Xyz Monsters, also most stall cards are bad now. Similar to Gravity Bind, which also went back to 3.
Lightning Vortex	Limited due to abuse with Sinister Serpent for cheap frying of the opponent's face-up monsters. It still saw some abuse since there were 2 Night Assailants still on the list. It finally came off the Limited status after Night Assailant hit 1 on the next list.
Mage Power	Was considered too strong back when beatsticks won Duels on their own. Equip cards are considered slow now and they most likely won't stick around with S/T removal cards being popular these days.
Magical Stone Excavation	Allows quick reuse of major Spell Cards. Its heavy cost is often circumvented in Diamond Dude Turbo Decks. Empty Jar Decks love this, but with Morphing Jar #2 and Morphing Jar Forbidden in the TCG, those Decks are unplayable now, so it came off the list.
Megamorph	Doubling original ATK can be a lot, sometimes enough to OTK. The drawback of halving ATK when you have more LP isn't too bad either as you can always equip it to your opponent's monsters. However, Equip Spells are still bad and have gotten worse now with s/t removal, also beatsticks don't mean as much anymore.
Mind Control	Unlike Change of Heart, you can't attack with or Tribute the monster, but you can still use its effects and it still can be removed via a Fusion/Synchro/Xyz/Link Summon.
Mystical Space Typhoon	Fast. Staple. 1 for 1 card.
Nobleman of Crossout	Was formerly considered to be too powerful back when most Decks couldn't do more than set a monster before ending their turn. Like Fissure (above), faster Decks that could cope with one for one cards like this were made over time, so this later came off the list.
Overload Fusion	Back then, Future Fusion comboed with this to provide a large beatstick; nowadays, beatsticks don't mean as much as they once did, and Future Fusion has been slowed down.
Pot of Duality	Lets you choose one of the 3 top cards of your Deck without losing hand advantage. Sets up for big plays. Adds a lot of consistency.
Preparation of Rites	Adds any Level 7 or lower Ritual Monster from your Deck to your hand, and can recycle a Ritual Spell card from your Graveyard. Mainly hit due to abuse with Nekroz. Pre-Preparation of Rites was designed to be a more balanced version of this card.
Sacred Sword of Seven Stars	Similar to Allure of Darkness, which is Semi-Limited in the TCG, but could be abused with Dragon Ruler monsters to trigger their effects when banished by this card's effect. However, with the Dragon Rulers now Forbidden, this came back to 3.
Saqlifice	Key Spell Card in Qliphort Decks. Prevents the equipped Qliphort from being destroyed in battle, also it gains 300 ATK and is treated as 2 Tributes for the Tribute Summon of a Qliphort monster, mainly Qliphort Disk (who then Summons 2 more Qliphorts from your Deck for an easy OTK). Can also add a Qliphort Monster from your Deck to your hand when it's sent from the field to the Graveyard. Searchable and reusable via Hidden Armory.
Shien's Smoke Signal	Grabs key Samurais like Kageki and Kagemusha. Came off the list due to the lack of Six Samurais in the meta now.
Smashing Ground	Fissure became Unlimited in the format before this came down, so this followed.
Spellbook of Fate	Chainable, powerful Spell card in Prophecy Decks that can get over almost anything. Can easily banish an opponent's card without Targeting by banishing 3 Spellbook Spell cards from your Graveyard (which can act as setup for Spellbook of Eternity), or can flip Spellbook Magician of Prophecy face-down to reuse its effect again. Can be recycled with The Grand Spellbook Tower or Spellbook of Eternity (after banished with another copy of Fate or High Priestess of Prophecy).
Spellbook of Knowledge	A quick draw-2. The sending to the Graveyard and the drawing happen simultaneously, so any Spellcasters' effects you trigger can't miss the timing. This means what appears to be a cost can be a direct benefit to you in the right Deck. Part of a highly splashable draw engine involving it, Spellbook Magician of Prophecy, and Spellbook of Secrets.
Spellbook of Secrets	Can search any Spellbook card with a different name of it, though you can only activate 1 per turn. Part of the draw engine involving Spellbook of Knowledge (above).
Swords of Revealing Light	Stalls for quite a long time. You can still attack while the opponent cannot. However, Spell/Trap removal is rife now, and this card won't stick around long enough to be a valid stalling method.
The Monarchs Stormforth	Allows you to Tribute monsters your opponent controls for Tribute Summons without targeting in an open Game state. Can even be activated during your opponent's turn to disrupt their plays with Ehther the Heavenly Monarch (Limited in the TCG), making Forbidden Lance the only surefire way to safeguard their field. Can be searched by Pantheism of the Monarchs(also Limited) or Tenacity of the Monarchs.
Temple of the Kings	Was formerly Forbidden due to being able to create easy Trap FTKs due to the lack of a once per turn restriction. Now the first effect has been errata'd to once per turn. Second effect is far more limited, and very hard to pull off in the current meta as consistently.
True Draco Heritage	Grants excellent advantage; it can potentially draw three cards in a turn, it can allow the player to Tribute Summon an extra monster, and if sent to the Graveyard, it can destroy a Spell/Trap, including the player's own, thereby either removing an obstacle or generating more advantage.
Union Hangar	A strong Field Spell card that can search out any LIGHT Machine Union Monster when it's activated and can also equip a LIGHT Machine Union Monster from your Deck to a LIGHT Machine Union Monster that is Normal or Special Summoned. Can be searched easily by Terraforming (Limited in the OCG). Mainly hit due to ABC Decks that were topping in the OCG, but with the likes of Ancient Fairy Dragon, Firewall Dragon, Terraforming, and ABC-Dragon Buster all hit there, they're nowhere near as much of a threat anymore.
United We Stand	Yes it makes monsters into bigger beatsticks, but with so many cards to stop it (e.g. Book of Moon, Dimensional Prison, any Spell/Trap removal at all, etc.) it came off the list.
Wavering Eyes	A powerful, chainable card for and against Pendulum Decks. This card's first effect allows easy burn damage, the second effect is versatile and easy to trigger, while the third effect provides easy, generic removal. It was especially powerful in Pendulum mirror matches, where the player with Wavering Eyes can devastate their opponent's set up while furthering their own plays, or even chain their Wavering Eyes to their opponent's Wavering Eyes, effectively rendering theirs useless. However, the release of Link Monsters and New Master Rule weakened this card's power significantly, since you must use your left and right Spell and Trap zones as Pendulum Scales now, and unless you control a Link Monster, you can only Pendulum Summon monsters from your Extra Deck one at a time.
Abyss-sphere	Great searcher. Special Summons ANY Mermail from your Deck. Can quickly Summon Mermail Abyssteus, Mermail Abyssmegalo, or Mermail Abyssleed for Rank 7 Xyz plays. Works very well with Mermail Abysslinde. Can be searched easily by Mermail Abyssmegalo. The lack of Mermail Decks being competitive caused this card to leave the list.
Bottomless Trap Hole	Very powerful 1-for-1 card. Banishes the monster upon Summon. Staple in most Decks. With the removal of Ignition Priority, this card has gotten better than before. Because it says "when your opponent Summons a monster(s)," if your opponent Summons multiple monsters at once (such as a Pendulum Summon), they all get hit, although in New Master Rule this is a lot more rare than it was before. Can be searched and reused by some of the Traptrix cards.
Call of the Haunted	Much fairer speed when compared to its Spell counterparts. It can't be abused multiple times per turn (unlike Premature Burial). It can only special Summon from your own Graveyard (unlike Monster Reborn). Played a crucial role in the Dark Scorpion/Makyura OTK. Like Magic Cylinder, top Decks eventually didn't play this card much, so it probably came off the list for the same reason. Most Decks that still run it wouldn't use 3.
Ceasefire	Chainable, defuses Flip Effects, and unlike its close cousins, checks both sides of the field. With swarming of Effect Monsters being all the rage these days, Ceasefire can be particularly punishing, dealing up to 5000 damage in one shot. With the release of New Master Rule and Extra Monster Zones, the maximum possible damage has been upped even further to 6000. Was once considered the best burn card in the game.
Compulsory Evacuation Device	An easy out to most monsters, which only became more powerful with the removal of the priority system of activating Spells/Traps. Can also be used on your own monsters to save them from Dark Hole, Torrential Tribute, etc.
Crush Card Virus	Could formerly kill almost every monster your opponent had in their hand, field, and next 3 draws when it was played, but now the effect has been errata'd so that it only destroys monsters with 1500 or more ATK on the opponent's field and hand when activated, with no further Lingering Effects, while also letting the opponent destroy 3 monsters with 1500 or more ATK from their Deck, potentially setting up their Graveyard. Furthermore, the opponent takes no damage until the end of the next turn.
Deck Devastation Virus	Can take out universal searchers and the monsters they bring out. Its tribute requirement can be easily met, especially in Dark World Decks.
Dimensional Prison	Easily banishes an opponent's monster with nothing but the opponent attacking. Gets over many monsters that have destruction immunity effects, as it banishes and does not destroy. Like Mirror Force before it, the current meta's far to fast for it now.
Drop Off	This card got Limited at the same time Time Seal initially got Forbidden. Then they realized that stopping a Draw is completely different from discarding a drawn card, in Decks which use the Graveyard more often. Also unlike Time Seal, it can't be chained, meaning your opponent can't lose card advantage in their attempts to target it.
Eradicator Epidemic Virus	Lets you look at your opponent's hand for 3 turns. Stops their Spells or Traps for a long period with an easy-to-pay cost in almost all Decks, with the releases of Number 66: Master Key Beetle and Number 85: Crazy Box. Extremely abusable in Dark World Decks with Grapha, Dragon Lord of Dark World, in Evilswarm Decks with Evilswarm Ophion, and in Dragon Ruler Decks and their variants with Number 11: Big Eye and REDMD. Two of these together can shut down all non-monster cards.
Exchange of the Spirit	Was formerly one of the most notorious FTK cards in the game, allowing you to Deck out your opponent with this card alone once you filled your Graveyard with 15 or more cards then flipped this, or activated it on your turn if you used Makyura (Forbidden) or Temple of the Kings (also Unlimited). Now, it can only be used once per Duel, and can only be used when both players have 15 or more cards in their Graveyard, not just you.
Geargiagear	Key card in Geargia Decks. Special Summons any two Geargiano monsters from your Deck at no cost, and it also increases their Levels by 1 for easy Rank 4 Xyz Summons, or for Synchro Summons with Karakuri Tuner monsters or Genex Ally Birdman (who is Limited).
Good Goblin Housekeeping	Back then, this Draw power was extremely good. It's bad now.
Gravity Bind	Stalls a lot, but Xyz Monsters aren't affected by it (Rank ≠ Level), also stall cards are bad now.
Icarus Attack	Powerful Chainable 2 for 2 card, which made Blackwings lethal. Now that they aren't topping much, and with S/T removal being popular, this came off the list.
Infernity Barrier	Powerful Trap card in Infernity Decks that negates almost anything. It's very easy for the opponent to meet its activation requirement since they don't have any cards in their hand most of the time, though near useless if they only have Infernity Necromancer, or similar monsters with low ATK. Can be searched easily by Infernity Archfiend.
Magic Cylinder	Negates an attack and inflicts major burn damage. Finishing move. Moved off the Limited List due to its lack of use in the meta.
Mind Crush	1 for 1 card. You don't really need to be a psychic to use this card, as you can easily call a card name after the opponent has used a search/retrieval effect, like Salvage, Machina Gearframe, Gadgets, etc. Allows you to see opponent's hand. Also, this card owns Ritual Monsters, when they activate their Ritual Spell Card, chain this and call the name of their Monster; a 2 for 1. The intended "downside" of calling a card wrongly can also benefit Dark World/Fabled cards. The lack of overall use in the meta perhaps resulted in it coming off the list. Like Magic Cylinder and Call of the Haunted (above), most people wouldn't use 3 anyway.
Mirror Force	Solid game changer, although with Starlight Road and THRIO out you need to be more careful when using this card. Most likely went to 3 due to lack of use in the meta, monster destruction being less powerful, and Spell/Trap destruction being more common. Also many better variants of this card have been released since.
Needlebug Nest	Mills the top 5 cards from your Deck to the Graveyard for easy Graveyard setup. Mainly hit due to abuse in Shaddolls, Lightsworns, and Dragon Rulers, all of which were topping in the OCG at that time. It may come back due to Infernoids increased relevancy, however.
Ojama Trio	Clogs the field with nigh-unusable Tokens. Key card in Burn Decks. Finally dropped off the list thanks to Link format, in which giving your foe Tokens is highly advantageous to them.
Reckless Greed	Because the skipped Draw Phases by its effect weren't accumulative, people wanted to stack these cards together...and then Unlimited again when fair shuffling techniques were enforced. JK, see why Upstart Goblin (above) was Limited.
Ring of Destruction	Was formerly Forbidden for causing too many draws in Tournaments and messing up Ranked Games. Instant destruction and serious burn. Lethal when combined with cards like Barrel Behind the Door or Spell of Pain. However, the effect has now been errata'd so it can only be used during the opponent's turn, can only be used on an opponent's monster with equal to or less ATK than the opponent's LP, and makes you take damage first, so it can't force tied games. Even after the balancing errata, though, it is still viable.
Royal Decree	1 card to continuously stop a large number of cards. Works well in Herald Decks to prevent the activation of Counter Trap Cards.
Sinister Shadow Games	Strong Trap card in Shaddoll Decks. Sends any Shaddoll monster from your Deck to the Graveyard AND can flip face-up a Shaddoll monster on your field, allowing you to get the effects of both the sent monster and the flipped monster. However, it's not a true Shaddoll card, and thus cannot be searched by Shaddoll Hedgehog, or reused by any of the Shaddoll Fusion Monsters. Besides, Construct's ban was a big enough hit to kill Shaddoll's relevancy.
The Transmigration Prophecy	OCG stall Decks used this with D.D. Borderline. Also, it was at 1 so it couldn't loop with another copy of itself. Pot of Benevolence does the same thing, but that can't be chained to an effect, and that banishes itself so it can't return another copy of itself. Came off the list due to looping it being too slow for the current meta.
Torrential Tribute	Punishes over-extending, but can easily be stopped with Starlight Road and THRIO in most situations.

In case someone somehow missed it. Click "Show" on the right side of the bar.

This list is for the people who are curious about why certain cards are banned/limited.

This list can also assist people before posting a prediction on the next banlist.

Please help out by pointing out changes that should be made in the list (if any) (please include reasons).

And for those who are wondering. No, I didn't make this list recently. It been on 2 other forums before. This is the most updated version of it as the other 2 aren't being updated.

See also: Historic Forbidden/Limited Chart. --  Falzar FZ  talk page  useful stuff    07:32, August 4, 2010 (UTC)

69.124.5.7 (talk) 15:57, November 7, 2012 (UTC)

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