Strings' Decks

Anime
Strings uses a Slifer Deck, which focuses on getting cards in Strings' hand to increase Slifer's ATK to be terrifyingly high and for the most part invincible in battle. Other than that, it appears to be a Slime Deck. The amorphous forms of the Slimes could represent Strings' mind being formed and shaped by Marik.

Strings' ultimate strategy is to get five specific cards out onto the field, which, in the manga and original Japanese anime, is called the "God Five" combo. These five cards are as followed:
 * "Slifer the Sky Dragon": The main attack force with near infinite attack power and which also weakened if not outright destroyed the opponent's monsters.
 * "Revival Jam": The ultimate defense, to defend "Slifer" in case necessary.
 * "Jam Defender": To allow "Revival Jam" to automatically defend "Slifer".
 * "Card of Safe Return": Every time "Revival Jam" is Special Summoned from the Graveyard, Strings must draw three cards, and "Slifer" gains 3000 ATK points.
 * "Infinite Cards": Removes hand limit, allowing "Slifer's" attack to climb virtually infinitely.

However, despite Marik's claim that this combo will allow "Slifer" to be indestructible, Yami Yugi proved otherwise, as he brainwashed "Revival Jam" and forced "Slifer" to constantly attack the reviving monster, forcing Strings to keep drawing until a Deck Out occurred, thus losing. Therefore, this combo's greatest weakness is that Slifer's power is limited by the number of cards within the player's deck.

Yami Marik re-uses various cards used by Strings during the Battle City finals.