Like that of many amphibians, the puffy, warted skin of the coleobasilisk exudes a poison. The transparent, oily secretion is one of the most deadly toxins known. It makes them allergic to bright light, and so they are only found above the surface of the lakes in which they dwell on overcast days.

The center eye of the three-eyed beast can charm the unwary. First victims will find themselves lulled, then sleepy. If a coleobasilisk manages to charm a victim, it will then creep up and rub itself against the skin of the victim, paralyzing and eventually killing it for later feeding.

Witch-women who dwell amongst the swamps bordering the lands of the Gray Elvani make of it a caustic skin potion that removes the signs of aging. They use it to maintain their own unnatural beauty and sometimes it finds its way into the Na-Market at Antra, where it sells for over one hundred gold zekzi a jar.

Sometimes the poison is also distilled and sold to alkhemetzi outside the swamps as well. It is the crucial ingredient in several sorts of potion. The capture of live coleobasilisks is potentially lucrative for an adventurer, if a somewhat dangerous enterprise.