In Chemical King's full debut (Adventure Comics #371), he is a member of the Legion Academy and works undercover to infiltrate the Legion of Super-Villains. After graduating alongside Timber Wolf, he becomes a full Legion member in Adventure Comics #372 (September 1968). Chemical King appears in few subsequent stories afterwards Plagued with self-doubts over the relative usefulness of his powers, he dies in Superboy and the Legion of Super-Heroes #228 (June 1977), when he sacrifices his life to stop Deregon, a Dark Circle agent and the governor of Australia, from starting World War VII, thus fulfilling the prophecy of his first posthumous appearance. Later the sorcerer Mordru resurrects Chemical King along with millions of other corpses as part of a plan to conquer the universe. The "zombie" Chemical King displays limited imagination with his abilities, igniting pockets of methane gas and starting fires. He is readily disposed of.
Chemical King is a mutant with the power to act as a human catalyst. He can speed up or slow down any chemical reaction; for example, he can cause iron to rapidly rust, or even burst into flames from rapid oxidation. His powers can affect the chemical reactions in the human body, rendering an opponent unconscious from shock, but take several seconds and can only focus on a single opponent at a time. Late in his career, Chemical King displayed the ability to change energy reaction rates as well, causing batteries to drain of power and force fields to decay. As the final act before his death, he used his powers to alter and absorb vast amounts of radiation capable of paralyzing Superboy. In post-Zero Hour continuity, he first appears in Legionnaires #59 (April 1998) then again in issue #64 (September 1998). He is not a Legionnaire, but instead works as a reporter.
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