Reading Jung Chang and Jon Halliday's very interesting Mao biography for the past few months. Boy, that Mao guy was a bastard. Hitler obviously front and center was evil and there are 4-5 Holocaust movies every Oscar season to tell us how. Stalin's evil has only really ever been captured in a few pieces of media. Death of Stalin is so very good.
But Mao...that guy...the paranoia, the emperor has no clothes aspects, the hangers on being worse and more venal, its just a lot. He killed more than both Stalin and Hitler so there is that.