Origin of the Crabs

Rouse suddenly let out a piercing scream releasing him from the paralysis of sheer terror in which those malevolent red eyes had held him. In panic he turned and tried to scamble up the slippery rockface. But his feet could not grip; slowly he began sliding back down, ever closer to the nightmarish form that was rapidly approaching, it huge claws waving in the air, its powerful jaws opening and closing in anticipation ...