I Say NEGADUCK Because even though he did not have any powers the other villains were afraid of him.
ABC (ended 1992)
The best villain has to be Negaduck!!! -lightning strikes everytime I say Negaduck's name-
Yes, Negaduck was the evilest of them all. He was REALLY vicious! He was the meanest, nastiest, and most dastardly and despicable villain in Disney history! He has a really deadly chainsaw that could slice you into pieces, a dozen bombs that will blow you into smithereens, a flamethrower that will barbecue you! If that's not enough, he can throw you off a building, knock you off a plane, try to steal your girlfriend and lure her back into a life of crime, flatten you with a steamroller, crush you with his nega-hammer, and even run you over with his motorcycle, the Troublemaker! -Yikes!
My favorite is Megavolt, if only because we both got teased and tormented in school. I felt so bad for him.
Runner up is Negaduck, for pure evil badness. And the Negaverse, which was awesome.