When meeting up with an informant, he fell into a trap set by Batman (Re-Verse) and Darkwing. They beat him up and then drop his tied up unconscious body into a drainage vat of chemical waste that washed him out into the river.
Jasper was a cop, he was investigating an underground criminal mastermind called the Master of the Night. He was close to under covering the Master of the Night true identity and leaking him to major crimes and deaths. Jasper was on his way to meet his informant "The ears", they were meeting at the Ace Chemical Plant. This turned out to be a trap, Jasper found "The Ear" dead in a chair with his ears cut off. Then the door closed behind him, standing there were two men. They turned out to be the Master of the Night and Darkwing. They beat him up, tied him up and then drop his tied up unconscious body into a drainage vat of chemical waste that washed him out into the river. The chemicals had an adverse effect on him: it dyed his hair green, bleached his skin white, and his lips were permanently stained red. Jasper was found half dead by his partner and girlfriend Harleen Quinzel. Deformed both physically and mentally, Japser, now a bleached white skinned madman, swore revenge on the Master of the Night and Darkwing stating he would "fight fire with fire", he would become The Joker.
Genius Level Intellect: The Joker is also very skilled in the fields of chemistry, genetics, and nuclear engineering. He also seems capable of mastering whatever he puts his twisted mind to when he wants to. Joker has a keen analytical and structured mind and is gifted at using distraction to implement direct attacks.
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