Worm

Worm decks aim to end their first turn behind a wall of face-down Reptile monsters, forcing the opponent into a field of hidden traps waiting to spring. The core gameplay is built on flipping Worm members face-down and then face-up again to repeatedly trigger their Flip effects. Worm Falco resets the board by flipping all other face-up Worm Reptiles back into face-down Defence Position, while Worm Erokin does the same on a single-target basis each turn. Worm Cartaros searches any Level 4 or lower Reptile Worm on its Flip, creating a chain of recurrence that keeps the hand stocked. Worm Illidan accumulates counters whenever a card is Set, then expends two at a time to destroy opposing cards, rewarding the passive, set-heavy style the deck naturally encourages.

The archetype's higher-end threats give it a path to close out games through combat pressure. Worm King can be Tribute Summoned by offering just a single Reptile Worm and then continues sacrificing teammates to pop opponent's cards, while Worm Queen converts that same cost into fresh monsters from the Deck. Worm Tentacles can attack twice in a Battle Phase by banishing a Graveyard Worm, and Worm Prince searches the Deck whenever it destroys something in battle. Worm Solid grows its Defence with each Worm in the Graveyard and punishes attackers by destroying a Spell or Trap they control.

Because so much of the deck's output depends on monsters being flipped face-up during the opponent's Battle Phase or by dedicated flip-back cards, the strategy is slower to get going when those setups are disrupted by monster removal that bypasses battle entirely.