Following the apparent death of Superman, four doppelgängers arrived, all claiming to be the real deal. However, the one imposter who managed to fool everyone was Cyborg Superman. Secretly the deranged Hank Henshaw, he had been transformed years earlier during a space flight gone wrong, and blamed his own mistakes (which included the death of his wife) on the Man of Steel, hence why he attempted to replace him. It was later revealed that the Cyborg had masterminded Mongul's devastating attack on Coast City, and it goes without saying that real Superman wanted a word with this guy upon his return. Of course, being able to transfer his conciousness between robotic bodies makes Henshaw nearly indestructible as he can constantly return to plague both Superman and his family (he most recently clashed with Supergirl in "The New 52).
