Synchro Monsters (Japanese: シンクロモンスター Shinkuromonsutā, abbreviated Ｓ（シンクロ）モンスター in card text since Duelist Alliance) are a type of Monster Card, first released in Starter Deck 2008. The color of their card frame is white. These cards are placed in the Extra Deck. To be properly Special Summoned, Synchro Monsters must first be Synchro Summoned. If they leave the Extra Deck without being Synchro Summoned, they cannot be Special Summoned while they are banished or in the Graveyard.