Original Airdate: ?/?/1984
Whiplash begs for the Royal Family's help when the evil alien monster Sh'Gora, foolishly brought to Eternia by Skeletor and Evil-Lyn, takes over Snake Mountain with plans to overthrow the entire planet. Zoar tells Adam to join Skeletor in a truce of good and evil to prevent Sh'Gora from conquering Grayskull. He-Man, Battle Cat, Man-At-Arms, Teela, Whiplash, and Fisto go to Snake Mountain and liberate Evil-Lyn, Trap Jaw, and Skeletor.
Sh'Gora unleashes his winged bats on them before bringing down the jaw-bridge of Grayskull and overtaking the Sorceress. He-Man, Skeletor, and their allies march into the castle, where a possessed Sorceress attacks them. Evil-Lyn frees her from the spell of Sh'Gora, who has gone to the travel corridor to create a gateway that will bring Eternia into his own dimension. The warriors hold him down long enough for Skeletor, Evil-Lyn, and the Sorceress to create a ball of power that opens a hole leading into outerspace.
The vortex drags Sh'Gora into it, but his tentacle latches onto He-Man, taking him with him, but Orko's lighting blast frees He-Man. He-Man tricks Skeletor into thinking a particular door is the one holding all the secrets of Grayskull; when the villains rush into it, they are transported back to Snake Mountain.
Synopsis by Zadoc Angell