The pathing rewrite ended up a lot more extensive than initially intended. Previously just another custom build of recast
was intended while keeping the usage the same however, in the end it became a full port of recast / detour as well some core modifications to it to have more control over the whole process. That obviously means that quite a bit more testing is needed.
The keep meshes will also need some adjustments as apparently one wall segment in particular seems to have a tiny gap that allows pathing through it.
This hasn't really been a problem in the past, as the keeps never changed and hence there was never line of sight into the keep. Now that holes can appear however, and hence guards can aggro, it's a bit odd when guards are able to walk through certain segments. Nothing game breaking as the intended hole from destruction is right next to that gap but it still seems quite weird when experienced first hand.
Another edge case is now around how we handle not finding a path: previously npcs just ignored that fact and kept wandering straight to the person for up to 2 seconds before retrying to get a new path.
This had the nice effect of not allowing well known safe spots from where you can just kill mobs because they can't reach you. However, this setting is a bit untenable with keeps and hence it has been turned off for now. That now means mobs that can't find a path / reached the end of their partial path will just stand there. There are a couple options on how to handle this and we'll most likely test a couple of them. A fallback in case the other solutions don't work as well as hoped would be to just apply this new behavior to pets and guards while keeping all other npcs on the old behavior.