2. Lex Luthor
Lex Luthor is the person that Bruce Wayne could have been had he chosen to follow his own selfish ambitions and desires rather than fight for the greater good. Just as Batman is central to the Justice League, so is Lex Luthor is a central villain in the DC universe. He is primarily an archenemy of Superman, but he has come into conflict with many other heroes including the Dark Knight. Lex Luthor has no superpowers but he is one of the most (if not the most) intelligent people in the DC universe. He has amassed great wealth through his intellect. He also has significant power and influence on society, and at one point he even became the President of the United States. Luthor has appeared in film in Superman I, II & IV (played by Gene Hackman) and Superman Returns (played by Kevin Spacey). These interpretations of the iconic character, although well acted, present him as a fast talking con artist with poor taste in henchmen rather than a criminal mastermind who is a real threat to Superman and the world.
Likelihood of appearing again Lex Luthor is to Superman what the Joker is to Batman. They are intrinsically linked. Although Luthor has not been confirmed to return in the upcoming film Man of Steel to be released in June, there is no doubt that he will return at some stage. If the Man of Steel is successful, it is very likely that Luthor will appear in the sequel.