I've had dreams of similarly abstract beings who have no faces. Those are the ones that make me wake up sweating. I don't have dreams of such beings often, but the lack of face, in my opinion, is most frightening about them--there's no telling whether the beings are to help or harm you. Their bodies may seem foreign, but with the right face, it's easy to know what the being is expressing. Without a face, its identity is seemingly lost, as something that exists while not existing at the same time.