Seriously, Pop Counters do nothing than input numbers. Add a feature, maybe in the next series of Bloons Tower Defense, such as; when a tower has a Pop Count of over certain numbers, 5k, 10k, 15k, you get extra defensive feature AND/OR are allowed to SELL for higher money. Also, I think of a degree-based range shoots for some towers; say..., a dart monkey tower (and all towers) currently are allowed to aim 360 degrees, and if it is to be set half that range, of 180 degrees, that tower will be granted a shooting speed limit of twice faster since its range has been halfen to only concentrate on a part of the pathway. The latter idea may be somewhat differing from the original idea of a TD but I'm only throwing the dices here and there.
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