Alexander Luthor Jr.(Pre-Crisis Earth-Three)

On Earth-Three, Alexander Luthor Sr. married Lois Lane and they had a son, Alexander Luthor Jr. During the events of Crisis on Infinite Earths, Earth-Three was destroyed. Alexander Sr. and Lois managed to send Alexander Jr. to Earth-One just in time, the only survivor of his home planet. Going through an anti-matter storm on the way, Alexander was aged up to adulthood physically and mentally. After helping to defeat the Anti-Monitor, Alexander brought the Superman and Lois Lane of Earth-Two and the Superboy of Earth-Prime into a pocket dimension. Years later, Alexander escaped from the pocket dimension and formulated a plan. He impersonated the Lex Luthor of New Earth, and recruited a new team of villains, The Society. He told them that he intended to build a machine to wipe the minds of the superheroes, but in reality he was building a machine to recreate the Multiverse. The real Lex Luthor tracked down his impersonator and had the Joker kill him so he could clear his name.