Devourer

This powerful entity originally spawned from the combined psychic energy of a half-dozen psychic monkeys whose minds had been linked by cybernetic implants.

The Devourer feeds on the mental energy of humans, transforming them into psychic zombies in the process. Immune to stun damage,these psychic zombies reproduce by coming into physical contact with sentient life, thus draining their mental energy and transforming them into additional zombies.

The Devourer possessed all the mental powers possessed by any of its zombie hosts and can use them through any other host. When the original psychic monkeys were freed, the Devourer disappeared and its known hosts reverted to normal humans. However, there is speculation that it may have retained sufficient power to preserve one or more of its 'host bodies' and is merely waiting the opportunity to 'infect' a mentalist of sufficient power to allow the Devourer to begin spreading forth once more.