You can just buy high level upgrades without spending any point on low level upgrades, but if you bought the low level ones, you won't have any refund. This seems -very- wrong.
You know what could make this more game interesting? If you had to control the falling Tetris pieces with the objective of forming lines, as usual, while still controlling the stick character trying to dodge the pieces. Multi-tasking is fun.
A bit too easy. BTD 3 took me some time to master, I haven't seem the game over screen on this one yet. Who would pay for glorified cheat codes in a easy game?
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