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For all three badges in one game: Play on the first level (hard), put tack shooters in all the round corners (fully upgraded) and throw a cannon in there semi-close to the beginning (upgrade it as needed.) That should hold them back for you to save up for a super monkey. Place a freeze balloon in the top left round corner (fully upgraded) and finally when you can afford it, place down a couple beacons to boost the range of the towers. Doing this I didn't even need to use road spikes to save myself once, and apologies if this is already known. Great game!
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This is a pretty good TD game, but playing it after the other games that come after it in the Bloons Tower Defense games it really doesn't hold up. No way to make it go faster, no way to choose "Strongest" for which bloon to attack, it's really small changes, but they're actually really important it turns out.
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if you want it insanely fast, once you get to about level 40 or 45 sell EVERYTHING and get all super monkeys. its actually really hard tho if you don't get a ton