He-Man in black magic and all forms of combat. He was also shown to be extremely cunning and intelligent. Though his origin was mysterious, and the cartoon described him only as a "demon from another dimension", a tie-in comic implied that Skeletor's true identity was Prince Keldor (the older brother of King Randor), thus making him He-Man's uncle. It was revealed in the animated motion picture "He-Man and She-Ra: The Secret of the Sword" that Skeletor was Hordak's right-hand man until his capture (Hordak referred to Skeletor as "my old pupil" and Skeletor's throne-room in Snake Mountain as "my old throne-room"
The Old Man of the Mountain (film) perform all of the music in the cartoon, including two songs Calloway co-wrote. The short begins with a live-action introduction of Calloway and his orchestra, who perform a short chorus of "Minnie the Moocher" (Calloway-Gaskill-Mills) before performing a vamp of the title song, "The Old Man of the Mountain" (Young-Hill (Brown)). As the cartoon proper begins, a lion on roller skates (made of rabbits) rushes from his guard post atop a mountain, racing into a nearby village shouting "Look out! The Old Man of the Mountain!" The lion's warning sparks a mass exodus of the other animals who pack up