Hey, can’t really see the solution you guys are currently working on. Just wanted to pitch in with an idea in case it might help: how it works is binding the overlap event of each cube to an event that checks overlapping actors starting from power source. So on every begin / end overlap, they update in chain and those that are not found to be connected are automatically told to turn off.
Just keep note that the last 2 for each loops can be done in 1 loop without casting or the branch. I’ll update it later 
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