NeoArkadiaUnlock over 10,000 cards. Some cards are exclusive to in-game purchases or event participation.
Master Duel even features Exodia!
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EDIT: From V-JUMP Play
Featuring more than 10000 different cards from the OCG/TCG!
In this game you will be able to use more than 10000 different cards from the very beginning of the service. Ranging from cards shown before like "Accesscode Talker" from recent years, you can Duel with a massive card pool that includes legendary cards like "Dark Magician" and "Exodia the Forbidden One"!
*Some cards can only be obtained in events or through purchases.
Further information about this game will be revealed later through V-JUMP Play.
V-JUMP Play also shows the individual clips from the TCG trailer:
Summoning Dark Magician: