Majin Buu is one of the strongest villains ... In DBZ, Kid Buu only appeared after Super Buu absorbed Vegito, and Goku and Vegeta freed everyone he'd absorbed from the inside.

A new character was introduced at the very end of the Majin Buu Saga ... After the fat Buu expelled evil from himself, it coalesced into a skinny Buu that went onto to absorb the other, forming ...