Want to explain what kind of behavior you are looking for?
Like how should the behave if they not run around randomly?
What i want to see to these kind of mobs is the ability to shoot them in the legs so they slown down a bit.
Very tedious to hunt them.
I kind of touched on it a little in the video.
But I believe that a natural approach would lead to a better end result.
They are herd type animals that graze. So, their initial state should be milling around grazing.
As someone gets closer it should perk their interest and they should go into a mode where they are trying to deciding if they think it is a threat or not. Possibly looking towards the alpha to see what they should do next.
If someone does spook them (by getting to close, moving to fast, shooting an arrow close ect) and they decide to run then they should all mostly go the same way (in a direction away from what spooked them). Following a leader/alpha or what ever. If nothing seemed to come from the possible threat then they should stop again shortly after and cautiously go back to grazing.
A deer that actually took an arrow though should act different. It could just run off on its own and have a whole separate set of rules. If it happens to be the alpha then all the other deer could still follow its actions. If not it could break off from following the alpha and do its own thing alone out of fear.
That shot deer should get a temp boost from adrenalin sending it fleeing quickly in one direction. But after that initial boost it should slow down greatly. If someone does get a good first shot on a deer then it should not be too overly complicated to finish the kill if they are able to keep track of them. Possibly there could be a bleeding type of effect based on how much damage the arrow did. With the deer slowing down more based on how much hp is lost. They could possibly even lay down in mercy mode if too much life is lost over time.
After the kill, the hunter could butcher the deer and go back to finding a heard again.