The Arendians are psychic parasite/vampires, that can posess human bodies and drain life force from others to sustain their hosts. They have little intelligence of their own, relying on the brains of their hosts. Their physical form is a glovwing fog.

Their home world has only scattered bands of human hunter-gatherers. They mostly infest animals. Their world has a portal, which under a brillant leader, they have organized a base.

GURPS Atomic Horror 42