Origins of the Joker from Batman

"In the batman comics, the tell of the jokers origins are revealed. The joker used to be a mercenary who was the best shot around. He started getting depressed with his work because there was no challenge. Well one day he comes across batman and finds his true challenge and decides to pursue it. So to go about challenging himself he kidnaps batman's girlfriend at the time. As batman is going to rescue her the joker kills her, batman seeing his loved one die in front of him throws two batarangs at the joker, cutting the sides of his mouth, giving him his scars.
Later in the same comic the joker is at a pharmaceutical plant for some reason. Some how he is knocked into a silo full of anti-depressants. The joker decides to accept death, and just before he's about to die he sees the grate in the bottom. It crosses his mind that he doesn't have to die, so he kicks out the grate and flows through the pipes that dump him out in the bay. The joker then swims ashore, his skin bleached white, his hair turned green, and his suit dyed purple. Laying on the shore he looks at the moon and sees a bunny on it. From then on the joker becomes the psychopath we all love."

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