Zane Truesdale

Zane Truesdale, known in Japan as Ryo Marufuji and nicknamed "Kaiser Ryo", is the top Duelist of Duel Academy when Jaden is in his first year. Zane serves as one of Jaden's friendly rivals during that year, though he takes a more brutal approach to Dueling after experiencing a transformation of mind during the next year. In subsequent years he develops fatal heart conditions and seeks an opponent worthy enough to give him his final and greatest Duel before he expires, though he is later revived under unexplained circumstances during season four. Zane is one of three people to have defeated Jaden in a Duel, the others being Kaibaman and Aster Phoenix.