Source: Bestiary 6, pg(s). 124–125
Exoskeletons are mindless undead raised from the hard parts of dead vermin like arthropods or shelled molluscs. Most exoskeletons are created by necromancers, but some arise spontaneously from places full of negative energy or are created by malfunctioning artefacts; feeding upon destroyed undead also sometimes causes an arthropod to become an exoskeleton when it later dies. Exoskeletons have become infused with evil and instinctually attack the living on sight, exploding in a burst of dusty remains when destroyed. Rarely, an exoskeleton is haunted by a stubborn soul that grants it intelligence.