A little on the easy side. Upgrades are NOT worth the money. Just buy 25 simple dart towers, then save the rest of your money for super monkeys. You can't lose. More upgrades and stronger bloons would make it better
Sometimes you just see it and other times you don't. I had to put it aside and pick it up a day or so later and then the impossible levels came easily.
The secret to this game is that your own soldiers are the enemy. If they breach, you level without collecting much gold for upgrades. Let the enemy slaughter your own guys and then you can pick the enemy off and get more gold. I just finished round 6 and have More Damage, Take No Damage, No Power Bar, and Double Shot.
It would be nice if you could buy something to increase your stamina. Also a boss would be nice. Good game, but short. Could use more upgrades of different types to choose from.
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