The Face-Eater, or F'Seeta was an ancient, intelligent entity.
The Face-Eater itself was a being that could control several shape-shifting creatures that could telepathically read the memories and emotions of their victims. It could also control the minds of the Proximans. (PROSE: The Face-Eater)
The Face-Eater was originally a cow-like animal selected for development by the Proximans as an experiment in creating a vast gestalt mind. After experimentation, its true physical form was a vast, leathery monster that absorbed almost all organic matter on Proxima 2. The Face-Eater was created with a mechanical control component, allowing the Proximans to force it back underground, before it was finally switched off and destroyed. (PROSE: The Face-Eater)