5 stars: Fun game. It can get a little grindy in places, but there's enough variety in turrets and strategy that it retains the fun factor. You can play it by just varying the basic types of turrets that you use, but the real fun is in stacking support towers and having the right combination of firepower. Most of my best attempts have had very few, yet very powerful, turrets working together. The sign of a well-balanced game.
3 stars: Great game for the first 2 worlds though you wont be able to finish the third without paying for emeralds. I am sure this is by design. I have finished each challenge with 3*'s and maxed out all the free emeralds possible though the upgrades are not enough to win the last challenge of stage 3 and unlock stage 4. Stuck and have to delete.
2 stars: The artwork is good, I love that it is in portrait mode. However not happy that during the first few levels it gives you lots of coins/gems but then levels get extremely hard requiring you to upgrade, which requires you to grind the previous levels which now give you only a few coins/gems. Seems like they just want you to pay for gems just to make any progress.
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