Super Mario - he killed a lot of turtles and innoncent mushrooms crying
Galbatorix from Eragon book series - he killed many dragons and their riders
Voldemort - scream
Jessie and James pirate they wanted to steal Pikatchu D:
In Disney, I think that Scar is who I would place at the top, with Maleficent second.
Scar I have up first because he essentially does the same things as Maleficent (gaining power through force, manipulation, etc) but he does this to his own family.
Maleficent comes second only because her characterization does not clarify if this is part of her (as in she came into being with the evilness) or if she grew into this. With Scar it seems like he chose his "evil".
I had this discussion a few years back and someone said that Ursula was the most evil of disney villains-but I can't see it. She was turned out of the palace and has been trying to get her revenge ever since. Whenever I see revenge as part of a villain's motive-I can't see them as completely evil.