if you don't choose the right upgrades, the first boss is impossible, so i would recommend adding an ability to reset your selections so that you can respend your points. that would allow a person to try different combinations
Ok just finished the medium challenge, and it was pretty tough. So, I'll share my strat.
Here's a picture for reference.
!http://i2.photobucket.com/albums/y37/Radeonrose/bloons2medium35.jpg!
I started out with the center cannon on the left side of the middle row. It lasted me until level 4, where I needed a tack at the end to catch a few stragglers. Level 5 was the same.
Around 5 or 6, I added another cannon next to the first one.
After a 3rd one, I added my first boomerang monkey in the upper left corner.
By the way, I never upgraded the cannons, but upgraded the monkeys to multitarget.
Essentially, the 'rang monkeys serve to destroy the blacks so the cannons can handle the rest. Tacks were needed here and there, but this worked.
I'd be interested in seeing other successful strategies outlined.
Heh. I beat the game...cheated a little...
Right click to bring up the flash menu, then move your mouse straight to a place close to the exit, and left click. Then move the mouse onto the exit. You win.
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