Majin Boo was created by Bibi-di as a weapon against the Kaio-shins. He defeats most of the Kaio-shins and was cursed as Fat Boo. Later, he was used again by Babi-di to destroy Earth. Boo went through various form changes (after absorbing Fat Boo, SSJ3 Gotenks, Mystic Gohan, Piccolo, and Vegitto) and even split into two good and evil beings. Fat Boo joins the DragonBall team. The evil Boo named Kid Boo was killed by Goku and was reincarnated later on as Ubuu.