Hints; Kill the birds flying by to unlock an additional gun. Don't bother upgrading guns. Purchase henchmen to defend your base instead and just collect coins, rather than shoot anything yourself.
Tip: Select a tower to buy, purchase an upgrade for an existing tower, then place the tower you have selected. Even if you can no longer afford that tower after the upgrade purchase, you can still place it.
Great game but, getting past day 14 is impossible. Needs some work on weapon availability, and upgrade prices. Enemy becomes drastically tougher and waves are too large after lvl 10. I want to love the game but lvl 10 and later ruin the game. 1/5 *Frustrating*
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