Best comic book villain?

[Henry]

Doom and Joker, for very different reasons.
Doom is narcissistic, but at least he’s competent. His subjects, oddly, love him to death, and he actually does right by them (most of the time). He’s a megalomaniac, but if you don’t care about pesky little things like personal choice, self determination, and freedom, he’d do a good job.

Joker is just plain sadistic and evil, but he’s insanely multifaceted; one minute, he’s using a crowbar to club your ward to death, the next minute he’s planning a ticker tape parade.

Comic Thanos gets “worst” villain from me, because he tries to kill half of all life basically because wants to impress a girl.

 

[Crimson Longinus]

This is easy. Magneto. Such a complex and tragic character that straddles the line between a here and a villain. My gold standard example of how to create great antagonists or indeed 'evil' player characters.

 

[Henry]

Galactus, since we are all ants to him in the grant scheme of things.

Galactus, in D&D speak, has an alignment of Neutral Hungry. We’re ants because we happen to be sitting on the cake on his picnic table.