BatMan

Batman

Story
When his parents were gunned down in front of him, young Bruce Wayne resolved to rid Gotham City of the criminal element that took their lives. He trained extensively to achieve mental and physical perfection, in addition to mastering martial arts, detective techniques, and criminal psychology. Dressing as a bat to prey on criminals' fears, Batman fights crimes with the aid of specialized gadgets and vehicles, operating out of his secret Batcave below Wayne Manor. In addition to this, he had a secret batcave hidden under Arkham Asylum, unknown to all but him and his butler, Alfred.

Joker
The Joker is an insanely homicidal super-villain who is considered by all to be Batman's arch nemesis and Gotham's greatest threat, whose white skin, green hair and blood-red lips belie the chaotic nature underlying his cartoonish-clown appearance. The self-styled Clown Prince of Crime has no superpowers, beyond a capacity for incredible violence, good combat techniques and a skill at creating deadly mayhem and holocausts. He frequently concocts elaborate schemes to entrap his arch nemesis, Batman. The Joker's insanity can be considered unique, for example not only does he think of Batman as his greatest enemy, but also as his best friend, ironically the only person Joker doesn't hate. Joker has a sadistic and sickening sense of humor and hedonism and is a complete sadomasochist, making him one of the craziest and deadliest criminal masterminds the world has ever known.

He is the main antagonist of the Christmas Eve and Arkham Asylum incidents. Because of this, the Joker is considered to be the main antagonist, mainly due to his unnatural relationship with Batman.

BackGround
Though Joker's background is generally unknown, he reveals a possible story to Dr. Harleen Quinzel in Batman: Arkham Origins. A miserably failed stand-up comedian, he was pressured into working with the mob by the Falcone Crime Family - in hopes of proving himself to his wife as a husband and as a father - forcing him to wear a suit, a bow tie, and a Red Hood with a similarly-colored cloak attached to it. They sent him on a string of robberies, which Batman was tracking. Eventually, they sent him to the Ace Chemicals building, where he worked as a lab assistant before turning to stand-up comedy. There, they were caught in security and a violent shootout ensued. But fortunately, the pre-Joker didn't receive any shots. During his attempt to escape from the chemical factory, he is chased by Batman, which ended with the pre-Joker jumping and falling into a catch-basin vat of toxic chemical wastes thinking he could escape captive by the Dark Knight. He is eventually sucked down a drainage pipe and is dumped in an alley behind the building. He rips the red dome off of his head and looks at the reflection of his new, disfigured face in a puddle. This accident, along with the man's misfortunes that day, drove him over the edge resulting in the birth of the Joker and the start of the career of one of history's most dangerous foes. This story is called into question, as Joker has given Hugo Strange multiple other stories. Joker himself admits that he doesn't exactly remember his own past, stating that he prefers to have a multiple-choice response.

From-GameNews.