This game is really good. A suggestion though, I think it might be a good idea to have a button that you can hold to repeatedly purchase a type of tower, this may be in but I can't seem to find the button myself. Also, a bug I noticed is that when the upgrade/sell icon is over a different tower, when I click on either button, it upgrades or sells the tower that the icon is hovering over as opposed to the tower I orginonally clicked. Great game though, keep up the good work!
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