A restart button would be nice so you can start over if you screw up. Also, reading the text before each mission set, I started setting up my towers on the wrong entrance because to me it read like they'd be coming from the south which I assumed would be at the bottom... maybe reword that a bit so you can tell easily which place the mobs are going to come from. On a side note, I am enjoying this TD, haven't really seen many I like recently. 3/5 so far :-) keep it up!!!
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