22. Venom

Superhero books are often about exploring alter egos, and it doesn't get much more direct in that regard for Spider-Man than when he faces Venom. Spider-Man's dark, violent and murderous counterpart, Venom came to be when Eddie Brock, a reporter with a vendetta against Spider-Man, found the alien symbiote costume Spider-Man had picked up during Secret Wars, only to discard it when he discovered its true nature.

With his hulking physique and monstrous, alien like mouth (complete with fangs and a drooling tongue), Venom, who has all of Peter Parker's powers, is like a distorted and scary funhouse mirror version of the black costumed Spider-Man, and his knowledge of Peter's secret identity allowed him to target his enemy in particularly cruel and dangerous ways.

Venom's popularity right out of the gate was huge - he was easily the most talked about new Spider-Man villain in years, which went hand in hand with the sensation caused by the evocative work of the incredibly buzzed about young artist who first drew Venom in The Amazing Spider-Man, Todd MacFarlane. The character was so popular that he suffered from over-exposure for a time, popping up so often in Spider-Man books and various mini-series that his impact was diluted. That over-exposure thankfully eventually stopped, and what remains is still one of the most notable and iconic Spider-Man villains ever.

Eddie Brock has gone through many changes and identity shifts through the years, and the Venom persona has not always been his. But while Eddie himself has gone back and forth between fighting for what he perceives to be right -- the "Lethal Protector" -- and outright villainy, it's inevitable that he eventually succumbs to his dark side, and fans are treated to another Spider-Man Vs. Venom battle.