While not having "Ojama" in its card name, "Ojamuscle" is treated as an "Ojama" card because it has 「おジャマ」 in its Japanese name. "Ojamuscle" was eventually given errata in the TCG to give it an "Ojama" archetype condition.
Some "Ojama" cards also support LIGHT Machine Fusion Monsters and the "Armed Dragon" archetype. This is a homage to Chazz, who used the "Ojama" archetype alongside the A-to-Z and "Armed Dragon" monsters.
"Ojama" monsters are humanoid creatures with large, pronounced and characteristic facial features. Each member wears a floral red bikini brief, including "Ojama Knight" who wears his over his armor.
Six unknown "Ojama" creatures appear in the artwork of "Ojama Country": a spiky flying light yellow "Ojama", a flat purple "Ojama", a fat lime green "Ojama", a spiky grey "Ojama", along with what appears to be a snake and a dog. The skeletal remains of some of these creatures appear in the artwork of "Solidarity".
The original "Ojama Trio" are often used as the butt of humor on several card illustrations, such as being hunted down on "Harpies' Hunting Ground", being tossed by "Man-Thro' Tro'", being used to practice boxing in "Ojamuscle", flattened on "Power Filter", falling into the canyon shown on "Nitwit Outwit", chased down by a shark in “Painful Decision”, etc..
All "Ojama" monsters have 0 ATK. Many "Ojama" cards fill up or prevent the use of the opponent's Monster Card Zones. There are three Main Deck "Ojama" Effect Monsters, "Red", "Blue", and "Pink" who help the archetype in general.
The name "Ojama" comes from the Japanese phrase Ojamashimasu (お邪魔します), which literally means "I am intruding" but is used to mean "sorry for the intrusion". It is usually used as a greeting when entering someone's house or room. "Ojama Trio" could be a reference to this, which has the Ojamas barge onto the opponent's field. Their name could also come from the word "Jama", which means "obstacle" in Japanese. The term "Jama" is also used to describe something or someone that is a nuisance or "in the way".
The main focus of the "Ojamas" is to generate enormous hand advantage and utilize the Field Spell to switch the ATK/DEF of all monsters on the field. Also, the "Ojamas'" swarming capabilities can Summon powerful Xyz and Synchro Monsters to dominate the field.
"Ojama Blue" is the linchpin of the Deck, along with the Field Spell, "Ojama Country". It is recommended to find ways to get "Blue" to the field as soon as possible to start the "Ojama" engine. "Blue" can add the Field Spell and another key card, "Ojamagic", straight to your hand; "Ojamagic" allows you to add all three of the Normal "Ojamas" to your hand at once so you can use them all in conjunction with power cards like "Polymerization", "Ojama Red", and even the infamous "Ojama Delta Hurricane!!".
Their biggest Fusion Monster, "Ojama King" has a whopping 3000 DEF, blocks off 3 of your opponent's Monster Zones, and can be revived every turn by "Ojama Country" just by discarding a single "Ojama" card. In the Graveyard, "Ojamas" can be revived by the Field Spell, "Junk Synchron", and the powerful "Tri-Wight".
While "Ojama" Decks can be formidable and very irritating for any Duelist facing them, they are not insurmountable. In fact, individual cards can seriously degenerate the soundness of these Decks. "Doom Donuts" will destroy every "Ojama" monster (including Ojama Tokens since all their original ATK are 0). "Deck Devastation Virus" can be equally as heady if not worse against "Ojama"s, possibly keeping them off the field for a few turns. It's true that destroyed "Ojama Tokens" will also mean damage for your opponent (via "Ojama Trio") but if your opponent can sustain the damage, their field will otherwise be fully open and ready for use.
The Special Summoning ability of "Ojama Red" can be intercepted with cards such as "Torrential Tribute", "Giant Trap Hole" and "Darkfall"; the latter-most card can be the most demoralizing as it can mill "Ojama"s to the Graveyard from the Deck, hence keeping the field empty longer and possibly making "Ojama Blue" and "Ojamagic" moot. Better yet, anti-Special Summoning support (e.g. "Fossil Dyna Pachycephalo", "Jowgen the Spiritualist" and the "Vanity" cards) can halt "Red" completely.
"Ojama" Decks rely on significant Spell/Trap support to compensate for the non-Fusion "Ojama"'s meager stats. Cards such as "Eradicator Epidemic Virus", "Royal Decree", "Trap Stun", "Secret Village of the Spellcasters" and perhaps "Magic Deflector" can put support in grave trouble.
Additionally, if "Ojama Country" is not on the field to give "Ojama"s an offensive chance, cards such as "All-Out Attacks", "Battle Mania", "Final Attack Orders" and "Staunch Defender" can possibly shave their numbers off the field and do serious damage. "Ojama" Decks that prefer to be high in DEF can also be defeated with choices like Defense Position-destroying card effects, "Cursed Bill" and "Evil HERO Inferno Wing".
In addition, cards including but not limited to "Non-Fusion Area", "Anti-Fusion Device", "Steelswarm Sting" and "Fusion Devourer" can forcefully boycott the "Ojama" Fusion monsters off the Field too, forcing the player to merely rely on the regular "Ojama"s or Xyz Monsters during the Duel.
- "Snatcher Easter Egg (Kojima Reference) - YouTube". YouTube. May 3, 2010. Retrieved October 9, 2020.