Superman #196

Two Supermen square off on this striking 1967 cover by Curt Swan and George Klein — one wielding a hammer that sparks on impact, both grappling a twisted steel beam as they strain against each other with matching capes and emblems. The cover's teasing headline asks readers to determine which is the real Man of Steel and which is "The Thing from 40,000 A.D.," making it one of those irresistible Silver Age mysteries that practically dares you to look inside. Wayne Boring and Stan Kaye bring Bill Woolfolk's far-future premise to life within, promising the kind of imaginative sci-fi storytelling that made Superman DC's self-proclaimed "World's Best-Selling Comics Magazine.