Darceus

Darceus is the evil counterpart of Arceus and the official mascot for Pokémon University 2. When Arceus hatched from its Egg, it also spawned his evil self. The fight was intense, until Darceus was excommunicated and send to the Pokémon World's limbo with help from the Creation Trio.

Trivia
Following the aforementioned storyline, it is patently clear that Darceus drew inspiration from Lucifer.