Original Airdate: ?/?/1984
Randor proclaims the first "He-Man Day" before a sudden earthquake breaks off a substantial part of Mount Eternia. The removed rock reveals a temple interior, and Adam, Teela, and Orko decide to investigate. Orko visits the temple and finds an interior protecting a little being trapped by a bell jar. Orko moves the bell jar, thus the Energy Beast springs forth. When He-Man and Battle Cat attack the Energy Beast, it decides to go to another dimension.
At Castle Grayskull, the Sorceress explains that the Energy Beast was created when the planet formed. The Energy Beast terrorized the Ancients until they found the secret of controlling the monster. She instructs them to search the temple in Mount Eternia for the Gold Chamber, which should contain the magic to control the Energy Beast. Adam, Cringer, Teela, and Orko climb into the Roto-Rocket, an experimental drilling machine, to locate the Gold Chamber, where a ghostly figure called the Spirit of the Ancients appears before them. The Spirit produces the Eternian Crystal, but Skeletor steals it. The heroes retrieve the crystal. Atop Mount Eternia He-Man manages to trick the Energy Beast into sealing himself inside the mountain.
Synopsis by Zadoc Angell