Yeah Saren!
How about Lord Lucien from Fable 2, and Jack from Fable 1?
Actually Jack of Blades is the better of the two... He wears an awesome mask, and no-one knows he is evil until the last part of the game. And then when you kill him, he returns as a DRAGON in the Expansion pack!!!
Ultimato
bowser shouldn't be on this listr because he golfs plays tennis rides go karts hell even plays baseball. kidnapping the princess is just what the group does for fun on the weekends.
albatross412 (Updated )
The golfing is stress relief. Despite that he sucks at it. Besides, he likes to mess up others with those deviant items. Who do you think owns those chain chomps? Baseball is a dying sport and he's playing it to rub it in our faces as we get sunburnt sitting in our seats waiting for the inning to end. That's just diabolical!
You should check out my list of favorite animes and videogame bosses.