While the Joker is a self-proclaimed agent of chaos who supposedly only cares about inflicting pain and causing destruction because he finds it hilarious, the revelation of his true motives says otherwise. The real reason the Joker is the way he is was revealed after he received a superpowered upgrade courtesy of a being more chaotic than he could ever dream of being, and those true motives are pretty embarrassing, as they go against everything the Clown Prince of Crime claims to stand for.
In the crossover miniseries Joker/Mask by Henry Gilroy, Ronnie del Carmen, Howard Shum, and Ramon F. Bachs, the Joker gets his hands on the titular Mask (of Jim Carrey movie fame) and is granted all of the powers the artifact offers each wearer. The Mask grants anyone who wears it invincibility as well as the ability to manifest objects out of nowhere in a twisted cartoon-like fashion, all to fulfill their subconscious desires. Since the Joker is basically the poster child for chaotic excess, the Mask just enhances his already flamboyant persona while making him virtually unstoppable.
Related: Joker Got the Perfect Name & Power by Crossing Over with Marvel
While the Joker doesn't change much after putting on the Mask in terms of personality, as opposed to previous wearers who were unrecognizable in their «Big Head» form, the Mask does uncover the Joker’s deepest desires and reveals the real reason he is a criminal mastermind. As Harley Quinn, Batman and others point out through the series, the Mask taps into the unconscious mind of anyone who puts it on and releases their pent-up desires. For the Joker, that pent-up desire is to run his own 24-hour broadcast filled with gags and criminality, constantly increasing the scope of his
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