Following the destruction of Ansem and Xemnas at the hands of Sora and Riku, Xehanort is revived. In response, Yen Sid decides to put Sora and Riku through the Mark of Mastery Exam in order for them to become full-fledged Keyblade Masters and counter Xehanort's threat. The Mark of Mastery will have Sora and Riku visit worlds submerged in sleep to "wake" them and restore them to their proper places. If they are successful, they will be acknowledged as Masters. In the end, however, only Riku passes while Sora fails the Mark of Mastery Exam. Then much to everyone's surprise, Lea summons a Keyblade. Sora parts with his friends and eventually ends up in Traverse Town, where he is greeted by bunches of Dream Eaters he had befriended on his journey. Back at the Mysterious Tower, Goofy and Donald talk about how long Sora's been away and how Lea has gone back to Radiant Garden while Riku is on an errand for Yen Sid. The two see Riku arrive and is surprised at who he had brought. Meanwhile, Mickey and Yen Sid discuss on how to combat the rise of the new Organization XIII without triggering a Keyblade War. Mickey says that with the revival of Organization XIII, they will attempt to collect the seven pure hearts of light, whom they will have to protect. Yen Sid calmly responds that he has already prepared for such an occasion as Riku comes into the room with Kairi, whom Yen Sid has heard can wield a Keyblade and intends to train her for the upcoming threat.
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