Medium level actually took the most tries, but all levels are beatable. Unlike the first balloon tower defense, there is no hurry to get the Supermonkey. The bombs tower are the key to beating medium and hard difficulty. If you placed them 3 or more together where all balloons bunch and meet up ( hard difficulty ), they will erradicate pretty much most "levels" of the balloons, leavings the rest of the balloons for the 8 directional spikes, dart monkeys, and the boomerange monkeys.

To beat the hard difficulty, you must first start off with the bomb tower on the bottom left, where both balloon pathways intersection. This will give you the most opportunities. Don't upgrade this tower earlier. Your 2nd tower should be on the right hand side around the middle in a pocket that covers top, left and right. This will get your started good. The third tower should be a boomerange tower and get multi target upgrade. because this tower has a cirucular range, it is good hitting balloons from two directions.

Spike towers are a must after level 30 to pop black, white, and rainbow balloons. Because your bomb towers cant hit the black ones, you must lay a spike to immediately pop a bunch of them. Keep using them. And use some monkey glue.

Most people cant pass the hard difficulties because they start with the regular dart towers. Start with the bomb towers.

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