The Toxic Avenger Part III: The Last Temptation of Toxie (1989)
Trailer
Toxie finds he has nothing to do as a superhero, as he has ridden his city of evil. So he decides to go to work for a major corporation, which he discovers may be the evilest of all his adversaries.
I'm amazed Red Letter Media hasn't looked at this lol.
Uncle Lloyd strikes again!