In the comics, Doomsday first appeared in Superman: The Man of Steel #17 (1992) and was created by Dan Jurgens. An alien scientist created an "ultimate lifeform" that would die and then was recreated stronger than its preceding incarnation. The super-evolved creature, programmed to destroy any opponent, gained the ability to evolve on its own and killed its creator. It escaped Krypton and eventually found its way to Earth, going on a rampage that took it to Metropoplis. Superman sacrificed himself to seemingly destroy the creature. Since then Doomsday has returned despite his apparent death, each time more powerful than last. He has also gained human feelings and sentience, and lesser versions of himself have been cloned. His power remains the ability to evolve any power or resistance sufficient to defeat him, combined with an accelerated healing factor. He possesses no human identity, unlike his appearance here.