Since the Golden Age of Comics, the Lex Luthor character has been the nemesis of Superman in particular and the DC Universe in general. More so than any other villain, Luthor has been the thorn in the side of the DC superheroes...often leading and directing the efforts of other villains.
But in many ways, Luthor is the villain that the heroes and their world cannot do without: he is the necessary evil.
For all the dastardly crimes he has committed, how many times has Luthor (in the comics, in the SUPERMAN movies, and even the JUSTICE LEAGUE animated series) also been the world's savior?
1. In SUPERMAN II (film), Luthor was instrumental in enabling Superman to deceive and defeat General Zod and his lackeys.
2. In CRISIS ON INFINITE EARTHS, Alexander Luthor of Earth-Three played a significant role in defeating the Anti-Monitor and saving the universe.
3. In THE FINAL NIGHT, Luthor rallied the resources necessary to preserve the world and devised the solution to the Sun-Eater problem (although it was Hal Jordan who actually made the sacrifice to save the Earth).
4. In the JUSTICE LEAGUE and JUSTICE LEAGUE UNLIMITED animated series, the Justice League needed Luthor to help them defeat the Justice Lords and, on a later occassion, Darkseid.
Even when Luthor helps the heroes, he always has an ulterior motive, but nevertheless, it seems that the heroes sometimes cannot do without Luthor.
The DC Universe does not have a Reed Richards type character: a super scientific genius and leader type wrapped in one package. Thus, Luthor often must assume the dual role of villainous enemy leader AND scientific savior.
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