 The idea that Miraclo was addictive, combined with the suggestion that Tyler himself was addicted to crime fighting, made Hourman one of the superhero world's first cautionary tales.Rex continued to fight both of his addictions throughout the rest of his appearances.His character was seemingly killed off along with other Golden Age heroes fighting a time-traveling villain named Extant, during the Zero Hour crisis, when Extant increased Rex's temporal rate to age him to death.