Nice take on the shootorial. The variety of items to pick up in addition to implementing color show creativity. The game itself isn't fun for long, but it is a good demonstration of your potential. Keep up the good work.
Control over the soldiers would be a nice addition. Concentrate fire would be useful, if the soldiers actually did it. They just happily shoot at meaningless targets while the artillery slaughter them. Simply an exercise in frustration.
Idea isn't bad, but balance is poor. The XP mechanic strongly encourages spamming the weakest unit. There does not seem to be any point in using anything but the strongest tower. As a result, most of the upgrades are pointless. The need for combined arms is usually what makes RTS-style games interesting.
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