Memory Moss
Presenting the most complex monster in a dungeon game to date: the memory moss.
HD 1/2 (1d3) AC 0 # App. 2d6
Can't move. Targets spellcasters mentally. Cunning save or lose all memory of the past 24 hours and it steals one of your Rituals at random. Stops attacking after a successful theft.
1-in-6 chance encountered memory mosses have already stolen spells. They form themselves into a copy of the victim's face, casting the stolen Rituals as Phrases if threatened. Eating the memory moss restores stolen memories and Rituals on a successful Brawn save, or deals 1d6 permanent Brawn damage on a failure.