Bring me glory in combat!
Henzell says...
  1. Crawl sometimes generates unusually hard monsters to keep you on your toes. The chance for a non-vault monster to be OOD is approximately 5.2% (3.9% on D:2 and 0% on D:1). OOD monsters come from between 1 (38%) and 5 (2.2%) levels deeper. Other times when something seems overly powerful, it's just a vault -- e.g. death yak guarding the lair.
  2. do {!source _apply_ood}

Information based on master branch and the great LearnDB.
© Dungeon Crawl Stone Soup, 2010.