Purple Lichen: AC 10; MV 0; HD 4; hp 30; THAC0 nil; #AT 0; Dmg 0; SA drain PSPs; SD immune to weapons; SW vulnerable to light; SZ L; ML 0; Int non (0); ALL N; XP 270; New monster.
This room is completely dark, and the walls are covered with purple lichen, a parasitic fungus developed by the ulitharid as a weapon to infect and destroy elder brains. The licken acts as a psychic sink, draining psionic points at the rate of 3d10 PSPs per round from any psionic creature within 10 feet. Every 10 points it drains causes it to grow 1 square foot. The lichen is susceptible to light and is rendered dormant when exposed to light or continual light spells. It dies if exposed to daylight for 1 round. It must be fed at least 1 PSP every day, or it dies. It is immune to weapon attacks but is affected normally by spells.
Originally appeared in Dungeon Magazine #33 (1992).