The Caulder Component was a serum invented by Chief Niles Caulder. Capable of providing extensive regeneration to the human body and giving enhanced cloning capabilities, it was initially stolen by Lex Luthor. Ironically, it was surprisingly stolen from Luthor by the Batman. It was later used by the Dark Knight to create clones of himself who would continue the role of Batman long after his death. However, after a clone was created, it required two years of actualization before it could actually become functional.