"Nekroz" (影霊衣 Nekurosu) is a Ritual Summon-based archetype comprised primarily of WATER monsters that debuted in Booster SP: Tribe Force with further support in Secrets of Eternity.
They're a clan that perfected magical rituals to weave the power of legendary monsters into armors via a magical mirror, and clad themselves into them. This power allows them to even control the power of the "Ice Barrier Dragons".
The "Nekroz" non-Ritual monsters are aged versions of established characters from earlier acts in the Duel Terminal storyline, associated with the "Gishki" and/or "Ice Barrier" archetypes.
The "Nekroz" Ritual and Pendulum Monsters are the "Nekroz" non-Ritual Monsters wearing armor based on monsters from Duel Terminal archetypes (usually Synchro Monsters), including "Ice Barrier", "Mist Valley", "Ally of Justice", "Dragunity" and "Fabled". Their effects, Levels, and stat lines are often similar to their original counterparts' effects. They share their Types as their original counterparts.
Some "Nekroz" Spells are based on established lore contents from in the Duel Terminal storyline associated with the "Gishki" and/or "Ice Barrier" archetypes.
"Nekroz" is a portmanteau of "necro" and "cloth/cross" ("Kurosu" can be translated to both words, both which fit the archetype's theme) refering to the armors (cloth/cross) based on legendary monsters (necro).
In their Japanese names, the kanji characters that the "Nekroz" reading is applied to, "影霊衣", literally means "Shadow Spirit Clothing".
"Nekroz" is an archetype focused on Ritual Summoning. The non-Ritual Monsters serve as conventional ritual support, fulfilling tribute requirements and/or fetching key cards to maintain consistency. The non-Ritual, non-Pendulum "Nekroz" monsters also have advantageous effects that are triggered when they are Tributed by a card effect, offsetting the costs of Ritual Summoning.
||Adds 1 Spellcaster "Nekroz" Ritual Monster from Deck to hand.
||Adds 1 banished "Nekroz" monster, except "Dance Princess", to hand.
||Adds 1 non-Ritual "Nekroz" monster from Deck to hand.
||Adds 1 Warrior "Nekroz" Ritual Monster from Deck to hand.
||Adds 1 Dragon "Nekroz" Ritual Monster from Deck to hand.
"Nekroz" Ritual Monsters have Levels ranging from 3 to 11. The effects of those ones with Level from 3 to 6 are used to suppress monsters Summoned from the Extra Deck, while the effects of those ones whose Levels range from 7 to 11 give to the player more card advantage, mainly by destroying and/or banishing other cards. In addition, all of them feature a second ability that can be activated by discarding them; these effects range from protecting and empowering on-field "Nekroz" monsters to reviving them and searching for resources. This remarkable property alleviates the recurring problem with Ritual monsters becoming dead draws when the player does not have means of Ritual Summoning them. In addition, the discard-based effects of those ones with Level from 3 to 6 are Spell Speed 1, while the ones with Level 7 and above can be activated during either player's turn.
The archetype's Ritual Monsters are all Nomi monsters that can only be Special Summoned by Ritual Summon. Additionally, all of them, save for the Levels 3-4 "Clausolas" and "Unicore", have restrictions or requirements for the Tributes (or equivalent monster costs) used for their Ritual Summons:
- Levels 5-6 ("Catastor", "Brionac"): Must be Ritual Summoned without using other copies of themselves.
- Levels 7-10 ("Gungnir", "Valkyrus", "Trishula", "Areadbhair", "Decisive Armor"): Must be Ritual Summoned without using monsters that share the same Levels as them.
- Level 11 ("Sophia"): Must be Ritual Summoned from the hand, by Tributing 3 monsters on the field with different Types.
||Adds 1 "Nekroz" Spell/Trap card from the Deck to the hand.
||During either player's turn, targets 1 monster Special Summoned from the Extra Deck, negates its effects and makes it ATK 0, until the end of that turn.
||Targets 1 "Nekroz" card in the Graveyard and adds it to the hand.
||Continuously negates the effect of monsters Special Summoned from the Extra Deck.
||Targets 1 "Nekroz" monster in the Graveyard and Special Summons it.
||If an opponent's monster Special Summoned from the Extra Deck battles a "Nekroz" monster, it is destroyed at the start of the Damage Step.
||Adds 1 "Nekroz" monster from the Deck to the hand, except another copy of itself.
||Targets up to 2 monsters Special Summoned from the Extra Deck and sends them to the Deck.
||Targets 1 "Nekroz" monster on the its controller's side of the field and prevents it from being destroyed during that turn.
||Once a turn and during either player's turn, by the cost of a "Nekroz" card on the hand, targets and destroys any card on the field.
||Banishes 1 "Nekroz" card from the Graveyard, negates an attack and ends the Battle Phase.
||Allows its controller to tribute up to 2 monsters from the field and/or hand in order to draw 1 card for each monster tributed.
||Negates the activation of an effect that targets 1 ally "Nekroz" monster.
||Upon its Ritual Summon, banishes 1 card from the opponent's side of the field, hand (randomly) and Graveyard (without targeting them).
||Targets 1 ally "Nekroz" monster and increases its ATK and DEF by 1000 until the end of that turn.
||Targets, destroys and banishes 1 opposing Set card.
||Tributes up to two "Nekroz" monsters from your hand or field, then sends an equal number of "Nekroz" cards from your Deck to your GY.
||Tributes 1 monster to negate the activation of a monster's effect and banishes it.
||By discarding itself along with a "Nekroz" Ritual Spell Card, prevents the opponent from Special Summoning from the Extra Deck during the Main Phase 1 this effect was activated.
||Upon its Ritual Summon, banishes all other cards on the field and from both players' Graveyard.
Their Ritual Spell Cards are very flexible and have additional effects and conditions that help to achieve the requirements of the Ritual Summons:
- "Nekroz Mirror" can banish "Nekroz" monsters from the Graveyard as part of the Tributes needed for the Ritual Summon;
- "Nekroz Kaleidoscope" is a unique Ritual Spell Card, that can be used to Ritual Summon any number of "Nekroz" Ritual Monsters, and can send, from the Extra Deck, a monster whose Level is the same as the total Levels of the intended Ritual Monsters; this versatility helps to maintain card advantage by keeping the monsters on the field and/or hand intact;
- "Nekroz Cycle" can Ritual Summon a "Nekroz" monster from the Graveyard, and is the first Ritual Spell that can do so.
Each of them also have a second effect that lets the player banish it and a "Nekroz" monster from the Graveyard in order to search for any "Nekroz" Spell Card, provided its owner controls no monsters.
- "Nekroz" Ritual Monsters are also vulnerable to effects that shut down in-hand effects, such as "Mind Drain", "Debunk", etc. "Imperial Iron Wall" can lock the Graveyard from the effect of the Ritual Spell Cards and the effects of "Valkyrus", "Trishula" and "Decisive Armor".
- "Masked HERO Dark Law" is also very powerful, since it will banish any Tributes for the Ritual Summons while also banishing the Ritual Spell Cards themselves after their resolve, making the Deck run out of resources in the long run. It also banishes a random card from the hand after a searching effect resolves, potentially crippling the "Nekroz" strategy.
- Any decks that can utilize "Number 80: Rhapsody in Berserk" can use it to banish the Ritual Spells from the Graveyard, preventing them from adding a new one from the Deck to the hand with their effects.
- Cards that negate the effects of Spell Cards, such as "Naturia Beast" and "Spell Canceller", are also major threats to this deck as they stop the deck from Special Summoning any of its Ritual Monsters (albeit they can be easily mitigated with the monster effect of "Zefrasaber").
- "El Shaddoll Anoyatyllis" stops "Nekroz" decks in their tracks as its effect forbids any Special Summoning from the hand or Graveyard with Spell or Trap effects, essentially making all three of their Ritual Spells useless in the hand.
- "Virus" cards such as "Crush Card Virus" and "Deck Devastation Virus" will work well against them due to the fact they must discard monsters from the hand and destroy the ones they control on the field. Using "Eradicator Epidemic Virus" and declaring "Spell Cards" can rid their hand of any Ritual Spells they may have, and send any other Ritual Spells they may draw to the Graveyard.
- It seems that the "Nekroz" armors have an innate ability to affect its wearer's age; the higher their Level, the older they become, and vice-versa.
- In Shurit's case, he's at his oldest when he wears the armor of "Areadbhair", as evidenced by "Nekroz of Areadbhair" having the highest Level (10) among his Ritual Monster forms.
- In Great Sorcerer's case, he's at his youngest when he wears Unicore's armor, as evidenced by "Nekroz of Unicore" having the lowest Level (4) among his Ritual Monster forms.
- Despite this, it seems that "Dance Princess of the Nekroz" and "Exa, Enforcer of the Nekroz" are unaffected by this phenomenon for some unknown reason, although Exa's body mass does appear to increase in his Ritual forms, with "Nekroz of Decisive Armor" featuring an especially bulky Exa.
- Despite "Nekroz of Clausolas" listing a "Nekroz" Spell/Trap in its text, currently there are no "Nekroz" Trap Cards.