Holiness
Version 0.32: This article is up to date for the latest stable release of Dungeon Crawl Stone Soup.
All monsters in Crawl are sorted into six fundamental categories of holiness: Holy, Demonic, Undead, Non-living, Plant, and Natural.
Monsters of each type of holiness have several attributes in common. For instance, all plants, undead, and nonliving are unbreathing. Only natural or plant monsters are vulnerable to negative energy. Demons and undead are automatically evil. See specific pages for more information.
From mon-data.h:37 (0.30.0):
MH_HOLY - irritates some gods when killed, immunity from holy wrath weapons. Includes good priests. MH_NATURAL - baseline monster type MH_UNDEAD - immunity from draining, pain, torment; resistance to poison; extra damage from holy wrath MH_DEMONIC - similar to undead, but no poison resistance, *no* automatic damnation resistance MH_NONLIVING - golems and other constructs MH_PLANT - plants