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The Skellirex is an undead skeletal dinosaur-like enemy that appears in Donkey Kong Country Returns and Donkey Kong Country Returns 3D. They have a small body and a large head. They first appear in the level Tumblin' Temple, but they mostly appear in the Cliff world. In Prehistoric Path, there are Skellirexes riding in Mine Carts.
Like most enemies, Skellirexes have a repeated pattern of walking left then right. If the Donkey Kong and Diddy Kong come in contact with a Skellirex, it bites them and they lose a heart. The Kongs can safely attack Skellirexes with any attack. By doing so, the Skellirex loses its body, and its head detaches and forms into a Skullyrex. The Kongs can instantly defeat a Skellirex by directly attacking its head, and they can also instantly defeat the Mine Cart-riding Skellirexes by jumping on them.
A Skellirex appears in concept artwork, where it more closely resembles a Tyrannosaurus and is missing its crest.