“An Ancient, Kryptonian deformity. Blood of my blood, born to destroy you! Your Doomsday!” - LEX LUTHOR

Doomsday was a mutated Kryptonian created by Lex Luthor from the corpse of General Zod in a long-forbidden ancient ritual, in order to bring down Superman. Capable of apocalyptic levels of destruction, Doomsday's might necessitated the forces of Wonder Woman, Superman and Batman in order to take him down. He was ultimately killed by Superman at the end of their fierce brawl, losing his own life in the process.