He-Man clash with Skeletor, in which Skeletor was flung deep beneath Castle Grayskull into a pit filled with steaming liquid. The film ended with a post-credit scene in which Skeletor emerged from the liquid and proclaimed, "I'll be back!". After the end of the Masters of the Universe toy line, Mattel attempted to revive interest in He-Man by producing a new toy line, entitled "He-Man". The accompanying storyline in the mini-comics packaged with the figures explained that He-Man had left Eternia and pursued Skeletor into the depths of space, where Skeletor had set his sights on conquering the distant world of
He-Man be a descendant of King Grayskull (a powerful barbarian and a hero from Eternia's ancient past), who sacrificed his life in order to save Eternia from the Evil Horde and originally wielded the Sword of Power. He was the original owner of Castle Grayskull; his sword was concealed in the castle for centuries before being given to Prince Adam, who inherited his ancestor's own power channeled through the sword (thus giving added meaning to the phrase "By the power of Grayskull..."). This action-figure line combined elements from the He-Man universe into a cohesive storyline with biographies on the figures' packaging.