Yu☆Gi☆Oh! Duel Monsters

Synopsis

Duke and Rebecca are about to reunite with Yami and the gang when they run into Mai and Valon. In order to prove himself to Mai, Valon accepts Rebecca's invitation to duel. Duke enters the fray as well. Despite their best efforts, Valon's mysterious Armor deck ultimately proves too strong to handle and they lose the duel, but are spared because Valon doesn't bother to use the Seal of Oricalcos on them. Meanwhile, Yugi, Joey, Tristan and Téa are close to meeting up with each other, while Kaiba and Mokuba head out on their private plane.

(Source: Wikipedia)