Not super special, but it is clever

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But why did you recenter the center location again? It's already in the middle, just an extra needless step.
I've never made deffence maps where I replace buildings under construction but I would have done something similar to detect them. I modified their health while under construction once for fun though.
I used to think 'Brings' would detect buildings whether they are done or not and 'Commands' only if they are done, but they both only work for finished buildings, I just never checked it till now

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