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Ok I'll start thinking on a workaround 🤞😅

I've used Google Chrome emoji 😁
About state we could have a user inferface to choose "this character/invoker/player" is == or != to this state and we could directly drop the state that we want to check...

Maybe "we" could add a check box, for any state, or if the user leave the field empty would mean == or !=  null 💪😏🤘

Sorry, but I still can't understand.

from Behavior I would need a variable like "SeenObject" that would be  filled automatically when the NPC see something.

I mean I know how fill a variable, but I can't access to what the NPC see with Perception!

Ok but, how I assign what the NPC Character see to the local Variable?