Cloaker

In the Dungeons & Dragons fantasy role-playing game, the cloaker is a large manta-like aberration with a set of black wings that cause it to resemble a cloak when at rest. These wings actually help the cloaker engulf its prey. A cloaker is usually chaotic neutral and they hunt together in small flocks. Cloakers are clever predators that can emit a subsonic moan that can unnerve, frighten, nauseate, or put foes into a stupor.