Monster intelligence

Version 0.30: This article may not be up to date for the latest stable release of Crawl.

If you were looking for the "Brainless" status condition caused by having 0 Intelligence, see Stat zero.

All monsters have a level of intelligence that determines certain behaviours, such as tracking the player, avoiding danger, and cooperating with allies. In general, a monster's intelligence is a secondary consideration compared to its physical and magical abilities, but it does have a number of effects, mostly in fairly specific situations.

Levels of Intelligence

There are three levels of monster intelligence:

1. Brainless intelligence: Plants, zombies, jellies, golems, elementals. ("Mindless")
2. Animal intelligence: Animals, insects, some non-zombie undead.
3. Human intelligence: Humanoids, some other powerful/magical monsters. ("Intelligent")

Effects of intelligence

The following is a non-exhaustive list of effects of monster intelligence.

Brainless

• Brainless monsters are immune to Anguish and Mindburst, cannot be pacified, and are unable to be bound by Yredelemnul.
• Brainless monsters will blunder into shallow water, shafts, and dangerous clouds (except miasma). Intelligent monsters will avoid clouds unless they are resistant, though a strong enough intelligent monster may charge through clouds if there's no better path.
• Non-brainless monsters will retreat if they can't reach you or shoot at you.
• Non-brainless monsters will often try to make space for their allies to attack you.

Intelligence

• Intelligent monsters search and travel more effectively, and will continue to hunt for you longer after hearing noise or losing sight of you.
• Intelligent ranged monsters will attempt to regain line of sight rather than charging directly at you.
• Intelligent monsters may be able to guess your location even when you are invisible.
• Only human intelligence monsters can be bribed or activate net traps.

History

• Prior to 0.28, the monster intelligence of your allies determined avoidance of traps (no effect on hostile).
• Prior to 0.26, butchering intelligent creatures would anger Zin.
• Prior to 0.17, there were 6 categories of intelligence: plant, insect, reptile, animal, human and high.
• Prior to 0.13 reptile intelligence and insect intelligence were one value, and Elyvilon could thus pacify insects. Also, friendly dumb monsters wouldn't turn hostile when damaged by ranged attacks.