De-Fusion

De-Fusion was released in the Labyrinth of Nightmare booster set, which debuted in the North American market in 2002 as the fourth core set of the Yu-Gi-Oh! Trading Card Game. As a spell card, it was designed to counter the Fusion Summoning mechanic by forcing a fusion monster to return to the Extra Deck, while offering the player the ability to special summon the original material monsters from the graveyard to the field. This card introduced a strategic layer to the game by turning an opponent's high-level monsters into a potential liability.

The card's design and artwork reflect the dark, mystical aesthetic prevalent in the Labyrinth of Nightmare expansion, which focused heavily on Fiend-type monsters and complex, ruin-themed spell and trap cards. The card's effect was intended to provide a versatile, high-impact tactical option during a time when Fusion monsters were becoming more prominent in competitive play. Upon its release, it became a staple utility card for players looking to disrupt board states and capitalize on the return of resource-heavy fusion materials.