Out of depth

Crawl tends to create many Out of Depth (OOD) monsters, who have spawned on a higher floor then where they are "usually" spawned. The source file mon-pick-data.h defines where is a monster's base floor is, so anything above that is technically OOD. The term typically refers to monsters which are much more difficult relative to where you are in the game, such as a sky beast on D:2.

Creation of Out of Depth Monsters

Like all monsters, out of depth monsters are spawned when the floor is generated. However, there are a few special cases with monster spawns, which can break the "normal" rules of generation.

• Monsters can often spawn in "bands", which have their own depth. Despite orc priests naturally spawning on D:4, it isn't uncommon for them to spawn in D:3 with an orc band.
• Monsters can spawn in manmade vaults. For example, one Lair entrance vault contains death yaks, which are very tough enemies for D:8.

Dealing with Out of Depth

• Check the monsters speed and range, and determine if you can just walk away. An OOD orc priest is extremely scary, with its 17 damage Smiting that reaches the entire screen. An ogre or hydra are 10 speed melee enemies, meaning you can just run away if you see them. The same applies to the 10 speed orc priest, but only if you can keep it out of sight (where monsters can't attack).
• Use your consumables! Especially if you can't escape.

History

• Prior to 0.21, monster spawning was used as a means to create out of depth monsters. If the out-of-depth timer went on too long, then it became more and more likely for these difficult monsters to spawn.