Z'tal Horde

Colonies of dun-scaled lizards called z’tals gather in a chirping mass. In doing so, they exude a slippery ooze and a noxious vapor. A z’tal horde remains undisturbed by creatures passing through it, but it can be dispersed by fire, acid sprays, or similar area effects.

    Effect: Each square of a z’tal horde is difficult terrain. A creature that ends its turn in a horde square takes 5 poison damage per tier. A creature that starts its turn in a horde square must make a saving throw before taking any other actions. If the saving throw fails, the creature falls prone. A close or an area attack that deals at least 1 point of damage destroys squares of a z’tal horde within the attack’s area of effect.
    Usage: The fast-breeding z’tal, difficult but not impossible to herd, sometimes serve as guardians for certain intelligent creatures. More often, a scavenging horde occurs naturally, drawn to the area around the lairs of large predators.

Published in Dark Sun Creature Catalog, page(s) 137.