CleverRaven/Cataclysm-DDA

The NPC AI system as it exists is a very ad hoc and messy state machine with no formal interfaces between decision making, information gathering, and actions.

Simply replacing this mess with a formal state machine would be a large improvement, but there's no reason not to take it further and move to a modern data-driven AI system.

See http://web.media.mit.edu/~jorkin/gdc2006_orkin_jeff_fear.pdf https://en.wikipedia.org/wiki/STRIPS http://alumni.media.mit.edu/~jorkin/goap.html https://www.gamedev.net/articles/programming/artificial-intelligence/the-total-beginners-guide-to-game-ai-r4942/