Which Dictator Killed the Most People?

I like this visualization, perhaps because its crude, almost childish look contrasts with the horror it depicts in such a simple way: Worldwide dictators ordered by the number of killings, one drop, one million dead.

Of course, the winner is Mao, followed by Stalin and then Hitler. I really hope hell exists and all of them are in there in some major eternal pain. [Wurstball.deThanks Karl!]