He-Man and the Masters of the Universe

Daimar the Demon (1x17)

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While bored, Orko casts a spell to bring a small, cute creature called Daimar, from a book about the dimension of darkness, to Eternia. But Daimar doesn't stay cute for long- he soon turns into a giant demon and is threatening to overcome Grayskull with his power, which Skeletor is also determined to acquire for himself!