<SSJ Gohans Hidden Power
Buu was created by Bibi-di for destruction. He defeated most of the Kaio-shins and was cursed into his fat form. Years later, he was unleased again by Babi-di and sent to destroy Earth. Boo went through various form changes (after absorbing good Buu, SSJ3 Gotenks, Mystic Gohan, Piccolo, and Vegetto) and even split into two beings. The fat one joined the good guys, and the evil original form Boo was killed by Gokou and reincarnated into Ubuu.