They inhabit worlds far from the stars, "the depths of the deepest space." For this reason, they often use portals to travel to other worlds and loot them in search of resources. They reside in cities of dark towers ruled by their elders. They possess unusual psionic powers, which help the Grioths against the beings of the Dominion of the Black, their sworn enemies.
They carry weapons (and sometimes armor) created from a transparent material called "voidglass", hard as steel and molded into shapes desired by beings from unknown worlds. The material echoes with the mind of the possessor, fortifying their mind. Grioths always fight to the death.
The expansion offers the name of a male, which is called Goladryth. Large and fierce, he knows the Aklo language.