He-Man and the Masters of the Universe - Season 2 - Eps 15: The Arena
Man-At-Arms has managed to make contact with a peaceful alien being called Om, hovering above Eternia. When Om is being welcomed by the people of Eternos, Skeletor invades the city with General Tataran and the Goblin Army. A fierce battle follows, and Om is confused by the way the two sides fight against one another, as his race knows no violence. So to see which side is wiser and stronger, Om selects He-Man from the side of good, and Skeletor from the side of evil, and pits them against one another in a fight to the finish.
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)