Limiting upgrades by basing them solely on completion of levels creates extreme frustration, because any work you do is a waste of time unless you complete a new level. It also tends to corner a player unless they know exactly how to complete each challenge and get mandatory upgrades that are disguised as open to the player's whim. In fact, a game of this nature is a study in how to control every single thing that the player does. Good luck.
A very nicely planned 'come back later' game. The interactive element is balanced with the automatic element perfectly. The characters and everything is minimalistic and still likable. Thanks.
Losing a level in a TD game should never leave you with no reward whatsoever for spending the time to play. In this game it is possible to spend hours retrying a level over and over without making any progress. Think that out. Great games though.
As you buy more items your speed and distance diminish because they work against each other. That is totally stupid. Upgrades should not hinder your progress in a game. 1/5
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