Join Sora as he joins Yugi and his friends as they try to solve the mysteries of the Millennium Items and try to find a way for Sora to get home.
A new evil arises for the forces of darkness as he thrusts six duelists known as the greatest heroes from their timelines and seeks to seal Kingdom Hearts away for good taking over time and space. Kairi puts her search for Sora on hold to help handle this crisis and Sora is forced to protect Quadratum forming an uneasy alliance with Yozora after their last clash.
Sora is weary of the whacked out card system within the enigma that is Castle Oblivion. As he ponders said system, a mysterious stranger in black, and the general state of his complicated life (cause let's face it, his life has become one big mess) he stumbles upon the King of Games himself, doing what he does best...play card games.