Extra Deck

The Extra Deck (エクストラデッキ, Ekusutoradekki), is a Deck where Fusion Monsters, Synchro Monsters, and Xyz Monsters, as well as Pendulum Monsters that would otherwise have been sent from the field to the Graveyard, are stored during a Duel. Any old card that still refers to the Fusion Deck applies to the Extra Deck. The Duel Disks are specifically shown to have an Extra Deck Zone compartment.