S1·E16 Mystique Explosion! The Great Katana World Battle!

Gao and his friends learn from the Seifukai that Doai is missing. They also learn that Zanya knows something about it and has found Genma's deck in the student council office. However, the deck is currently in the possession of Zanya's little brother, Akatsuki, who wants to give the deck back to Seifukai but is nowhere to be found. So, while Zanya fights against Jin in the last semifinal match of the ABC Cup, Gao and the rest try to search for Akatsuki. Sophia locates and gets to Akatsuki first, and she then takes him to the student council office. Gao and company track them down but see Akatsuki returning to Zanya, who defeats Jin. Afterwards, everyone regroups, and Akatsuki gives the box containing Genma's deck back to Seifukai, but everyone is shocked when they discover the box is empty. Back at the student council room, it is revealed that Sophia has taken the deck...