Manually collecting your rewards, and a more involved resource system helps to set this game apart from the otherwise saturated Tower-Defense genre. However, the process of building new towers, combined with a build delay and short breaks between rounds leaves this component feeling more frustrating than challenging. Beyond that, the xp system ought to use damage dealt rather than kill count for awards to towers: this allows the xp system to have a real effect on the alternative difficulty modes. As it is, with only 12 waves of enemies, only a handful of towers will level up more than twice. For the few towers I looked at, they all seemed to gain ~60% DPS for a speed upgrade, but only ~38-40% DPS for a damage upgrade. Unless there are enemies with natural armor that ignores low damage shots, there is no reason for such a significant disparity.
This game is not balanced, a bit too hard in the start, the "mouse over resources" thing is annoying... however, since the developer makes such a nice break from all-the-same TDs (experimentalism), and the game CAN be improved (maybe this version, maybe a future Zack's HW II...), I give a fair 3/5. ***BY THE WAY*** Kongregate, please, stop spoiling the comments. We see the comments while the game loads, and we want to see NEW comments, not the same top-rated. We understand you put this kind of "karma" to ease your lives and our lives, but make newest comments default! :D
 "Zack's Hardware"){kind=icon}