Lichentrolls

They cling to the walls of caverns, indiscernible from natural growth until they move. Their skin is layers of fungal growth with striated patterns. Not actually a single creature, the lichentroll is a symbiotic relationship between a fungus and magically attuned algae. There is no light in the deep for which a normal algae to photosynthesize, but there are other forms of energy that emanate through the earth. Those forces feed the lichentroll, allowing it to slowly rebuild itself even in the midst of combat. But they are more than eager to feast on warm flesh of all manner of creatures.
Geographic Distribution