"Masquerade of Madness!"
*While attending a masquerade party, Bruce Wayne, Dick Grayson, Zan, Jayna, and Jimmy Olsen fall victim to a spell used by the sorcerer Felix Faust. Faust explains that he has cast a spell on the party-goers to help him gain special jewels that are owned by his victims. Before he can fully execute his plan, the Super-Friends arrive and he is forced to enchant party guest into evil doppelgangers to battle the heroes. *Source: DocRx8482
Note: Bizarro, Swamp Thing, Man-Bat, the Demon Etrigan and Solomon Grundy are doppelgangers.