How do I add the local value of one to another instance?

User points an object via pathfinding towards a designated area. In this area a max amount of 20 smaller objects are present. When the pathfinding object arrives in the area, 10 of the 20 objects move towards the main object and 10 should get added to the main objects variables. The area should then substract 10 from its local variable indicating how many smaller objects are present.

Ive tried several ways of making this work, but I cant seem to get it. The values never balance out. What would be the best way of dealing with this scenario? I hope its clear

Not really clear. A capx would help, otherwise we have to re-create it from scratch. Can you post what you've tried?

So the main object has one instance variable? (you mention 'the main objects variables', plural)

How does an 'area' have a variable? And do you really mean local variable, or instance variable?

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