A man of true intellect, Jonathan Crane fell from grace when he became absorbed by his own experiments dwelling into fear and the incredible effects it can have on a person's psychological condition. Bullied throughout his youth, Crane seemed to conquer his own fears by becoming a master at such a natural and primal feeling through his research. Having developed an incredible gas agent that amplifies a person's worst fears and brings it to life in a horrifying fashion in his or her mental state, Crane guised himself into the terrifying image of The Scarecrow.
With his research the only motivating factor in his life, Scarecrow feels nothing but delight when he sees his countless victims' minds break into insanity and death from his weaponized fear toxin. Having been recruited by The Joker for one of his more brutal plans, Crane uses the opportunity to perfect an even more lethal dose of his signature fear gas. He hoped that not even the The Dark Knight would be able to withstand its effects and planned to unleash it into Gotham City to break the soul of every citizen forever.
Despite the enhanced toxin, Batman managed to overcome his fears once again and put an end to Crane's plans. Mauled by Killer Croc, Scarecrow disappeared for years, preparing the most deadly strains of his toxin imaginable and biding his time as he planned a massive operation with the help of a new villain, the Arkham Knight, to tear Gotham to shreds with fear and condemn the rest of the world into oblivion. Consolidating most of the villains and their gangs under his leadership, Scarecrow initiates his plans to destroy the legend of the Batman once and for all. [Source: wikia]
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