Devourer

A Devourer is a special kind of fiend from the Abyss. It is neither entirely Demon nor Undead, but a terrible combination of the two created by Orcus , the Demon Prince of Undeath. It is capable of creating a vortex of soul-rending energy around it, and, if an enemy falls, it can “Devour” that enemy, trapping it inside its open ribcage. If that enemy dies while inside the Devourer, it empowers the fiend and is regurgitated as undead.