Majin Buu is resurected when tons of energy in tranfered into his ball. Ok, that didn't sound right, let me reword that. When tons of energy is transfered into the egg he sleeps in. That's better. He kills hi master, Babidi, and does his own thang after that. He befriends Hercule Satan and vows to kill no more. He assissts the z fighters in fighting Kid Buu in the final battle.