He is an unhinged serial killer from Earth-2 who became a metahuman speedster after being affected by dark matter from the Particle Accelerator explosion during his electroshock therapy treatment, leading to him becoming a notorious supervillain who terrorized Central City and pretended to be "The Flash" of his Earth to inspire hope, only to rip it away. After finding out he was dying from cellular degeneration caused by his own speed-enhancing velocity serums, Zoom discovered the multiverse and began exploring it to steal the speed of other speedsters to cure his condition and become the fastest speedster in the multiverse, eventually targeting Barry Allen of Earth-1. After his plans to destroy the multiverse were foiled by the Flash and he was defeated, the Time Wraiths located and captured Zoom, imprisoning him within the Speed Force and, as punishment for his actions, ironically transformed Zoom into the guardian of the Speed Force's rules; the feral Black Flash. He is the arch-nemesis of Harry Wells, Jay Garrick and one the Archenemies of Barry Allen (alongside Reverse-Flash, Savitar, Clifford DeVoe, Bloodwork and Negative Speed Force).