Tetsuo forms a Dueling Team with Kotori, Takashi and Yuma, called Team ZEXAL. Yuma is accompanied by a Dueling Ghost called Astral, but he can only be seen by Yuma. By that way, when Yuma talks to him, the others think he is talking to himself. This, in addition with Yuma's arriving late for the team's first meeting, makes Kotori and Takashi worry about Yuma being the leader, and Tetsuo challenges him to a Duel - if Tetsuo wins, he will be the leader. Yuma accepts the challenge, and wins, so that others accept him as the leader.
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