Sartyr, known as Kabayama (樺山 Kabayama) in the Japanese version, is a character in Yu-Gi-Oh! GX Spirit Caller. He is the game's incarnation of Sartyr from the Yu-Gi-Oh! GX anime.
Professor Sartyr can be found in the Duel Academy Reference Room, where he gives the player Duel Puzzles and tips for using certain cards. Outside of the Duel Academy building, he can be found in the areas surrounding the Yellow dorm.
The player can Duel Sartyr after they learn about Duel Spirits. Defeating him several times can lead Sartyr to give the player a Ra Yellow uniform, saying he wished the player was in Ra Yellow.
- Sartyr uses this Deck at first.