There should be a button to quickly purchase all upgrades for an unit, currently it just takes too much time to purchase like 30 upgrades for 50 units (that is 50x30=1500 times upgrading an unit, while it could just be 50x..) I hope this will get implemented soon :) Great game! 4/5 untill it gets some updates :)
Also would like every unit to have an upgrade after level 7, not just some random units.
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