Pilaf

Pilaf is a major antagonist during Dragon Ball. He is a small, impish demi-human who craves nothing more than power and dreams of ruling the world. He is an emperor in that he has a crown and a castle. He rules over an empire known as the Reich Pilaf, however the only members of this evil empire are his two followers Shu and Mai. He collects all of the Dragon Balls once, but is foiled by Goku, and his friends. A second time, he is stopped by the Red Ribbon Army, and a third time, he releases Piccolo Daimaou, who betrays him soon after. At the beginning of the Dragonball GT, Pilaf accidentally wishes for Goku to be turned into a young kid with the Black Star Dragon Balls, setting into motion the events of the entire series.