The Dark One

The dark one is the antagonist of the final game in the big chungus series. He can take the body of anyone and is the most powerful physical being in existence. He has existed since almost the beggining of time and is almost pure evil. To defeat him, big chungus must find a way to somehow defeat him. When not in another's body, he is an invisible smoke cloud.

He is eventually defeated with the power of Uno.

This is his main theme:

https://youtu.be/9TTnTu3ql_g