Out of all the games, which bosses made you rage quit (meaning quit the game out of pure frustration to people who don't know)? For me it was:
KH: Clayton in Deep Jungle
KH2: Barbossa in Port Royal, Demyx in Hollow Bastion, and Xigbar in TWTNW
358/2: Leech Grave in Halloweentown, Ruler of the Sky in Neverland, and the sand lion thing (can't remember the name) in Agrabah
BBS: Xehanort on Terra's story, The whole Olympus Colliseum time match on Terra's story (not really a boss but still...URG), and Vanitas on Ventus