The Secret of Grayskull is the 104th episode of He-Man and the Masters of the Universe. (Ink & Paint DVD booklet summary: Skeletor sends the fiery-spider fireworks towards the Royal Palace, and while the Heroic Warriors deal with this threat, Orko receives scolding from Man-At-Arms causing the little Trollan to leave. Skeletor witnesses Orko's unhappiness and attempts to rid Eternia of his presence forever by disguising himself as a genie and telling him that everyone, including Orko himself, would be better off if he were to return to Trolla. Orko's decision is a tough one, but even after it is made he soon finds himself aiding Skeletor in an attack on Castle Grayskull!)