The Snake deck showed up in GX—used by upperclassman Seika Kohinata in later arcs.
As a "NPC" deck, it actually got an unusual amount of cardboard—more than some protagonist builds. But calling it a "deck" is a stretch; under real Yugioh rules, it had no shared archetype tag.
The manga called it "Snake," but not a single monster actually had "Snake" in its name. Yet the effect text often said "Snake deck," which is confusing.
Take Viper's Grudge, which Snake River just used. In the manga it Special Summoned a Level 4-or-below Snake from the deck; the printed card standardized it to any Level 4-or-below Reptile.
Summon pool massively buffed—generic Reptile support. But the trigger got nerfed hard: manga version triggered on any Reptile being sent to GY; real card requires battle destruction.
"Viper's Grudge: Special Summon a new snake. I bring out a second Black Mamba!"
The same black snake, mark II, slithered out in a cloud of poison.
[Black Mamba ATK 1300]
Kira frowned.
By manga text, Viper's Grudge triggers off any Reptile going to GY and is Continuous with no "once per turn."
Which means his Reptiles become functionally immortal—every attack only feeds him more deck access. The more you fight, the more he snowballs…
And since it's "sent," tributing likely counts too.
That can generate a lot of advantage—must be removed fast.
"I set two. Turn end."
Snake River: "My turn. Draw!"
Before he could act, Kira moved.
"I activate the Trap: Vampire Takeover. If I control no cards and all face-up monsters I control are Zombies, I can activate this from the deck…"
The deck auto-searched and ejected a card. Kira pulled it, his deck auto-shuffled.
A hidden slot popped open; he slid the card in, and it locked.
"Field Spell—Vampire Kingdom—activate!"
A crimson moon rose, blood-red mist billowed. A jagged castle heaved up under the moon's glow, its silhouette etched in gore-lit light, like a clawing giant.
"You activated a Field from the deck?" Snake River frowned.
"Not just that—Takeover has more."
He took a card from the GY and revealed it.
"Special Summon one DARK 'Vampire' monster from my GY in face-up Defense. Naturally, it's the one Gozuki sent last turn."
He slapped it down.
"Vampire Grace, in defense!"
[Vampire Grace DEF 1200]
"So easy to bring out a Tribute monster?" Snake River grew more serious. "As expected of KaibaCorp's lapdogs—you've got some skill. But 1200 DEF won't save you.
Then I summ—"
"Hold up—your Standby Phase isn't over."
Kira tapped a button.
"I activate my other set: the Trap Vampire Awakening!"
Snake River's normal summon stalled, and he shot Kira a look.
Whose turn is this, yours or mine?
"Awakening: Special Summon a 'Vampire' from the deck; it's destroyed in the End Phase."
Kira drew the ejected card.
"I Special Summon Vampire Duke."
[Vampire Duke ATK 2000]
"Another Tribute that fast?" Snake River scowled. "But it self-destructs—no threat."
"Vampire Duke: when Special Summoned, declare Monster, Spell, or Trap; your opponent sends one of the declared type from the deck to the GY.
I declare Spell."
Snake River thought, then sent a random Spell.
"And?"
"In that moment, Vampire Kingdom triggers," Kira said. "Once per turn, if a card is sent from your deck to the GY: send a DARK 'Vampire' from hand or deck to the GY."
His deck ejected another Vampire; he fed it to the GY.
"Then destroy one card you control—goodbye, Viper's Grudge."
Blood-mist arrows whistled from the crimson fog, riddling the trap with holes.
Snake River's face finally changed.
"So that was your target…"
Now his monsters lost their immortality and he couldn't chain Reptiles from deck at will.
"Alright—Main Phase resumes. It's still your turn. Go ahead," Kira gestured.
Snake River: "…"
So you do know it's my turn.
"Hmph. I Tribute my Black Mamba to Tribute Summon—
—Level 5: Urubonus, the Avatar of Malice!"
[Urubonus, the Avatar of Malice ATK 2000]
If memory served, the printed version can Special Summon itself by tributing a Reptile you control—doesn't use up Normal Summon, a buff over the manga.
"Urubonus attacks Gozuki! During battle, the monster battling Urubonus loses 300 ATK/DEF!"
[Gozuki ATK 1700 → 1400]
The serpent bit into the minotaur's arm; he roared as his body rotted and split.
[Kira LP 4000 → 3400]
The printed card's aura debuffed all opponent monsters by 300 while it stayed—another buff.
And it had a third effect the manga lacked: by tributing a monster you control, reduce all opponent monsters' ATK/DEF by the tributed monster's ATK until end of turn.
An epic upgrade from the source.
Kira narrowed his eyes.
Whoever this guy was, his deck had serious R&D potential.
Polish this list, publish a few papers—another heavyweight result.