I think you should be able to unlock the things that you have to buy with kreds. For instance, if you pop this amount of bloons than this upgrade or new track becomes available to you. That would make the game ALOT more playable since people wouldnt have to spend money on it.
HOLY CRAP!?!?!?!?! I made it all the way to round 105!!!!! 321100 RBE!?! I had 15 sun gods, 6 ships, 7 mortars, 5 gluers, 8 cannons, 30 odd wizards, 20 tack shooters and 2 planes. All fully upgraded.
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