What episode of Yu-Gi-Oh gx did jaden vs evil Jesse?

You're likely thinking of the episode where Jaden Yuki faces off against Jesse Anderson, possessed by the spirit of Yubel. This happens in Season 2, Episode 112: "A Duel of Souls".

It's a pivotal episode where Jaden confronts his former friend, who has become a dark reflection of himself. Jesse, controlled by Yubel, is fueled by a dark desire for revenge, leading to an intense and emotional duel.