- You shouldn’t be casting to Controller, as that will cast to a player controller, rather than an Ai controller. I’ve attached a picture showing two common setups.
- Yes, each Ai must have it’s own controller. The Ai controller, the behavior tree, the blackboard, and everything related to them are instanced when you create a new Ai character. This really makes sense when you think about it. How would your Ai behave as individuals if they all shared the same Ai tree and controller? Also, it should be noted that when you spawn your Ai in blueprints, you also have to spawn the default controller, or your Ai simply does nothing.
There are some good in depth tutorials on the Ai controller on youtube that’ll step you through the process of building some cool stuff if you’re interested in learning more.
Also, would you mind marking my answer as correct if it’s helped you solve your question?