In these 1960s stories the Legion of Super-Heroes meets the team of villains who never lose! Plus, witness "The Revolt of The Super-Pets"! Discover "Chameleon Boy's Secret Identity"! And unravel the mystery of "The Legionnaires Who Never Were"! Collects stories from Adventure Comics #361-380, Action Comics #378-392, Superboy #147, and Superman's Pal, Jimmy Olsen #106.