Doomsday. He killed Superman and when they brought Superman back (which was bullshit), Doomsday was still alive in space after Superman chained him to that rock. Superman is basically an invincible alien who can't die but Doomsday killed him.
Lex was badass because he actually thinks he is a good guy, not in the movies of course but in the comic book
Great Thread! Marvel -Loki, or Thanos (With the Gauntlet),Apocalypse, Carnage, Red Skull DC- Joker or Darkseid But I can't choose between Thanos or Apocalypse