S1·E38 Behind the Mask of Masquerade

Alice appears to be disappearing all the time. Dan goes to talk with Marucho, Runo, Shun, and Julie and ends up finding Alice! Alice won't explain anything and leaves. Later, Joe receives a message from Masquerade, and Dan decides he'll take over to fight Masquerade with Drago to end it once and for all with Masquerade. Dan wins and offers Masquerade to join the Battle Brawlers to help defeat Naga. But Masquerade refuses and takes off his mask. It is revealed that Alice was Masquerade the whole time!