Thread:Trans1000/@comment-5334494-20130111025303/@comment-5056929-20130115014606

That's because an unupgraded dart monkey's dart pops only one bloons per dart, you can't say much about that. Each upgrade describes any additional things that happen to the dart like making it able to pop 2 or more bloons or getting rid of them completely (Spike-o-pult). This doesn't just apply for dart monkeys but other towers like monkey aces, describes the pattern in which the darts are been shot and how many each can pop along with the altering effects corresponding to their upgrades.

This brings me back to my point that the upgrades themselves already describe the projectiles.