Ok, so the towers on the upgrade screen appear to correspond to the numbers of them you can have. Three towers is the total number you can have out on the field.
I know it's rather old now, but could you get someone to edit or do the text for you if you make another game? I mean "Upgrade the damage of the leader's defense" ?
What do the upgrades actually do? The heart one seems obvious, but the other one...? And the three towers in the top left of the upgrades? O.o The tutorial is lacking and I'm on level 7 and still getting the help popup.
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