10. Killer Croc,
because if you have ever played and Arkham game and seen Killer Croc you know what I mean.
because he is as smart if not smarter than Batman, does all that he can to achieve his one goal, to save his wife.
8. Two Face,
because he is a symbol of all of Batman's failures in trying to bring criminals to justice.
because he is a massive mob boss and his umbrellas pack a punch.
because she is a love interest of Batman, and she tries to appeal to him, right after she gets caught.
because he can become anyone and anything he wants to.
4. Prometheus #2,
because he was the criminal opposite of Batman, criminal parents killed in an alley trained to become a master criminal to fight justice.
because he has uncovered Batman identity, before having it beaten or tricked out of his mind, also broke Batman's back.
because he tries to drive Batman insane, and broke Batman's mind.
because he broke Batman's one rule.