 In 1944, the magical imp Mister Mxyzptlk, Superman's first recurring super-powered adversary, was introduced.Superman's first alien villain, Brainiac, debuted in "Action Comics" #242 (July 1958).The monstrous Doomsday, introduced in "" #17–18 (Nov.-Dec. 1992), was the first villain to evidently kill Superman in physical combat.