The Harvest abilities have a field called "Damage to tree", you can Set that to 0.
You can also Periodically restore the amount of gold in your Gold Mines or give them a huge amount of starting Gold:
hi! I need a endless gold mine, how can i do it? Thanks.
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Greetings, So i'm trying to make some small ruins and ruin settlements, with secret door's and boss rooms... So I'm looking for some tips when making terrain and doodads for ruins... And I wanna make a so to say "inf goldmine" of course meaning it's gold supply doesn't end. So how do i do it...
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But you'd probably have to trigger everything yourself if you wanted to mine from a Gold Mine without subtracting resources from it. That may be a bit of a challenge to do because there's no Event for detecting when a Gold Mine has been mined from as far as I know. If there is, you could adjust the Gold of the Gold Mine in response to it being mined.
A unit from your race gathers gold from a mine -> Set gold of mine to gold of mine + 10 (add back the gold taken).