SUPERMAN 214 (February 1969)--1st story, "The Ghosts That Haunted Superman" by Bates, Swan and Abel; cover art by Neal Adams:
The Man of Steel is not cowed when he's haunted by the spectres of three of his dead foes--the Composite Superman (Joe Meach), Metallo (John Corben) and Zha-Vam. Knowing that they can't possibly be the ghosts of those adversaries (ghosts don't exist), Superman calls out the real antagonist, who turns out to be an unassuming, young fellow named Nador.
When this young chap tried out for membership in a super-hero club called the Omega Commandos, the others would not let him in because they didn't like his looks. After he begged them to accept him, he was set the challenge of bringing Superman to his knees.
Although Nador has failed at this task, the World's Greatest Super-Hero nevertheless accompanies the lad back to the Omegas' clubhouse. They are all so impressed by Superman's visit that they let Nador into the club. Superman hopes that they have learned their lesson not to judge people by their looks.