A batman villain with split personality and no dress sense!
Originally name Harvey Kent, he was renamed Dent, because two people in the DC universe with the name Kent confused fans. He was the district attorney for Gotham City and a close ally of both Batman and Commissioner Gordon. Who can deny that there were probably some pretty whacky parties when they were chums?
"Whaddaya mean you forgot to call the stripper?"
Unfortunately, there was a little incident in court (of all places for an attorney to be), involving the mob boss, Salvatore Maroni, and a bottle of acid. This obviously ended badly for Harvey, sending him mad after seeing half of his face had been disfigured. He became a schizophrenic villain named Two-Face. Obviously this act of violence was seen by many as aggresive, but maybe Maroni didn't realise it was acid. Maybe it was meant to be a joke, and someone gave him the wrong bottle.
He doesn't really have any. Unless you count being utterly cuckoo as an ability. I like to think that it is, but that just helps me get through life. During the Batman: Face to Face story arc, it is revealed that Batman has trained Dent extensively in:
"He also tends to carry with him a large assortment of conventional weaponry, including guns, knives, rocket launchers, and poison gasses." (Wikipedia) Is poison gas conventional? Is there somewhere to check? Maybe a supermarket or something.
Here we have a villain who could go both ways (tee hee), he could either be super badass or ultra lame, depending on which version you look at. On the one hand, he can be a devious maniac who just has no control over what he does, letting himself become a slave to a coin. He murders, steals and pretty much fucks up Gotham royal! On the other hand, he does this:
You can blame two people for that. Joel Schumacher and the person who uploaded that video. Either way, make sure you pick someone. Use a coin if it helps.
To make Two-Face a true Batman villain, the writer must take into account his sad history. The fact that he was the District Attorney and a close friend of Bruce Wayne means there will always be a sympathetic twist. Hell, it could even mean there's a chance for redemption, which oddly enough, was written into the story of "Arkham Asylum: A Serious House On A Serious Earth".
WARNING: FROM HERE ON IN, THERE BE SPOILERS!
Basically, at the end of the novel (which is brilliant, by the way), Batman is trapped in Arkham with all of the lunatics he's locked up, including Two-Face. For his therapy, the doctors took away his signature coin, and replaced it with a six sided die, followed by a deck of Tarrow Cards, in an attempt to give him the ability to make decisions on his own. Unfortunately, it backfires, and due to the complication of the cards, he has trouble deciding the simplest little things, like going to the toilet, or performing Ebony and Ivory by himself.
"...live together in perfect harmony..."
So, Batman finds Two-Face's coin and gives it back to him, declaring that he should be the one to decide Batman's fate. Two-Face states that if the coin lands scarred side up, Batman dies, but clear side up, he goes free. After flipping the coin and declaring that Batman should go free, it is revealed that the coin, in fact, landed scarred side up.
YARGH. SPOILERS BE OVER!
So, for Joel Schumacher to take the character and turn him into a bumbling moron, a Joker rip-off so to speak, but with none of the class, is just diabolical! He might as well become a Batman villain himself!