Krag
From superman.nu: Supermanica
Krag
Krag arrives on spaceship with marking that pointed to the planet Mercury. After disembarking, he presents himself as a Mercurian that had learned English by watching the earth with "ultron telescopes and radio receivers". He displays powers equal to Superman and after helping some crooks rob a bank, he claims he is an outlaw that wants to be "King of Crime". To be able to meet the current Crime Czar, he challenges and defeats Superman. Soon after he is taken to the mob king where Krag unmasks him and takes him to the police.
Superman then reveals it was a robot all along which he controlled by remote control and ventriloquism, and he often switched costumes and makeup. (Act No. 165, Feb 1952: "The Man Who Conquered Superman!")
