Extra Deck Single's
The Extra Deck:is a Deck where Fusion Monsters, Synchro Monsters and Xyz Monsters are stored during a Duel. They are separate from the Main Deck, and you can search through it to find a Fusion Monster, Synchro Monster, or Xyz Monster that you need. There is a 15-card limit to the Extra Deck, regardless of how many Fusion Monsters, Synchro Monsters, or Xyz Monsters you include. The "Maximum of 3 Rule" for cards of the same name still applies.