He-Man and the Masters of the Universe - Season 2 - Eps 45: The Problem with the Power
Skeletor tricks He-Man into thinking he has accidentally killed a man and, consumed by guilt, He-Man transforms back to Adam and drops his sword down the abyss of Grayskull, deciding he is no longer worthy of Grayskull's powers. Skeletor then opens a portal to the goblin world, enabling General Tataran's army to enter Eternia, with possibly enough power and strength to conquer the planet. Can Eternia survive without its greatest hero... and will Adam realize he has been tricked before it is too late?
About He-Man and the Masters of the Universe

Title: He-Man and the Masters of the Universe
First Air Date: 1983-09-05
Last Air Date: 1984-12-08
Status: Ended
Rating: 7.293/10 (from 374 votes)
Language: EN
Seasons: 3
Total Episodes: 130
Network: Syndication
Genres: Action & Adventure, Animation, Sci-Fi & Fantasy, Kids
Production Companies: Mattel, Filmation Associates
Synopsis
When Adam, Prince of the planet Eternia, raises his magic sword he transforms into He-Man (the most powerful man in the universe). With his allies and friends, he battles the evil Skeletor and his minions to protect the secrets of Castle Greyskull.
Cast

John Erwin
He-Man / Prince Adam / Ram Man / Beast Man / Whiplash / Webstor / Faker / Granamyr (voice)

Alan Oppenheimer
Skeletor / Battle Cat / Cringer / Man-at-Arms / Mer-Man / Buzz-Off (voice)

Linda Gary
Teela / Evil-Lyn / Queen Marlena / Sorceress of Castle Greyskull (voice)

Lou Scheimer
Orko / King Randor / Stratos / Mekaneck / Man-E-Faces (voice)

Erika Scheimer
Arcadian women (voice)