In Game Tips:
You only need archer tower to beat the game. You don't need to upgrade them, just spam them in the map to create a powerful defense.
Build archer tower as soon as possible when you have 50 coins available.
Do not upgrade archer tower, just create them. Every upgrade of any tower will increase it's tower upgrade cost, it is more cost efficient if you build another level 1 archer tower.
Cannon Tower gives aoe damage but the firing rate is too slow while Icy tower only slows 1 enemy at a time.
At early phase of any levels, put the archer tower at a good spot. When you survive that early phase round, you can put archer towers at any position as long as it can hit enemies.
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