The Most Evil Badassery Villain ever created in an Anime?

I think kira is also pretty badass but by the end hes just insane. Father from Full metal alchemists is pretty scary too for the fact he manipulates people and is more intellagent than many humans but is not a human. I think all the bad guys from full metal are kinda cool. "When you notice an insect on the ground, do you stop to consider it a fool? The life of an insect is so beneath you that it would be a waste of your time to even consider judging it. That would be an accurate summation on my feelings towards these humans. „ ~ Father Pretty evil dude

i could see Aizen sousuke but then again the hogyoku probably played a part in making him more evil than he really is naraku from inuyasha is a baddie that comes to mind

Knives from Trigun. He believed since he was a plant that made him a superior being. He prosed was it immoral for him to kill the humans, because as a superior being he should dicate morality.