Belial

Ultraman Belial (ウルトラマンベリアル Urutoraman Beriaru) was a very powerful Ultra Warrior, until greed overcame him and he tried to steal the Plasma Spark. After his failure, he was banished and transformed by Rayblood into an Ultra Reionics. His assaults against the Land of Light ended in failure after being sealed away by Ultraman King, later on foiled by Ultraman Zero thousands of years later during his freedom. He would later establish an empire in Another Space before Zero foils him again, resulting in his death. As a lingering spirit, Belial sought the help of several aliens and possessed Zero but his defeat allowed him to be revived.