While I think Satan is still #1*, I'd like to return to Superman for a moment. Supes gets rewritten pretty often.
Not only has Supes gotten rewritten by DC comics several times- including other-dimensional versions- each of his cartoons, live-action shows and movies has featured revisions of some kind. Essentially, each time a production company recasts Supes for the screen, the character changes, too.
However, the was also an interesting period of time when Superman was dead. Not only were there "other" Superman types in DC's line, other comic books launched their own versions of "Superman".
Part of that is because Superman has become one of superheroic comics' archetypes. He had previously been copied by Fawcett's Captain Marvel, and later, by Marvel's Hyperion, and versions of him pop up all over the place: Captain Thunder, Mon-El, Ultra Boy, all of the other Kandorians & Marvels, Power Girl, Ultraa, Icon, Supreme, Titan, Gladiator, etc., each with their own unique spin on the legend....and too many to name.
You'd be hard pressed to name a 4-color comic book world that didn't include a Superman type as part of its timeline, even if he were not active at the time of the main storylines.
* on this particular list!