Not evilest (genocides, infanticide, and the like are no fun to read or to think about), but toughest, strongest, most dominant. How do you become the Doctor Doom Supreme of this universe?
You don’t have to explain how you accomplish your task, just what you would do.
Fun answers encouraged; don’t be a bummer. (marking NSFW just in case to make mod’s lives easier)
You have to come in at least a few episodes/chapters after the protagonists adventure starts, though, otherwise you get immediately murdered for character development.