[Fledermaus]

Wasn't Dr. Doomsday (? guy in iron mask face the Fantastic Four fought) also a common villian for many Marvel characters?

[Richard Kimball]

The character was Dr. Doom. I've mentioned on several threads, but Lucas stole just about this entire character in making Darth Vader. Doom was one of those villians that was better than the heroes he faced (not a "good" character, but a brilliantly devised and well-thought out character. He guest-villianed in several different comics. I remember Daredevil crossing him once, and I think Captain America.