These creatures have the appearance of giant sock puppets, about the size of an adult human. If the creatures are killed the outer skin/sock can be removed, revealing the giant forearm and hand underneath. The underside of the creatures is black and burnt, as if the forearm had been cauterised to prevent blood loss.
Each group of sock puppets appears to be telepathically linked, or even to share a single mind. They have almost human-like intelligence.
Sock Puppets live in a dark, foul-smelling lair called an Arm-Pit.