Detective Comics
Detective Comics is an American comic book series published by DC Comics. The first volume, published from 1937 to 2011 (and later continued in 2016), is best known for introducing the superhero Batman in "Detective Comics" #27 (cover dated May 1939).
Batman of Zur-En-Arrh
Batman of Zur-En-Arrh first appeared in "Batman" #113 (February 1958), in a story titled "Batman—The Superman of Planet-X!". It was written by France Herron and drawn by Dick Sprang. In the story, Tlano, the Batman from Zur-En-Arrh, brings Earth's Batman to his planet to help him battle giant robots piloted by an unidentified alien race. While on the planet, Earth's Batman discovers he has "Superman-like" powers through similar means of the Superman of his world. The end of the story leaves it ambiguous to the reader whether Batman's adventure was real or a dream.