Old Kai

Old Kai is freed when Gohan accidentally breaks the Z Sword during training on the Sacred World of the Kais. Despite his comical appearance and tendency to ogle women, Old Kai demonstrates knowledge and abilities far beyond those of the current Supreme Kai, Shin. His most important contribution is performing the Ultimate Unlock ritual on Gohan, a painstaking, multi-hour ceremony that draws out every last drop of Gohan's latent fighting potential. The resulting "Ultimate Gohan" form is powerful enough to dominate Super Buu without any Super Saiyan transformation.

Old Kai also sacrifices his own life to restore Goku's, allowing the Saiyan to return to the living world to fight Kid Buu. He later becomes a permanent advisor to the Universe 7 Kais, offering guidance during the events of Dragon Ball Super and providing exposition about divine hierarchies, the nature of the gods of destruction, and other cosmological details. His fusion with a witch millions of years ago (which occurred accidentally through Potara earrings) explains both his unusual appearance and his unique magical abilities, making him one of the few characters in Dragon Ball whose backstory involves involuntary Potara fusion.