In Yu-Gi-Oh! GX Tag Force, Seydina is the leader of the Six Attribute Deck Masters, a group of Obelisk Blue students who each wield a Deck of one of the game's six Attributes. The rest of the group consists of Truly, Celia, Brown, Dante and Rock. Despite their supposed status, they give less of a point bonus for defeating them than most other Blue students.
In the mornings, Seydina and his group can be found at the Duel Field, while after class they are outside the Blue dorm.
The player is able to give Seydina sandwiches. The following tables detail how much he likes or dislikes the sandwiches.