30649947 | Added on: November 29, 2014
This game does get hard very quickly... definitely not for players unaccustomed to tower defense games. However, the upgrades (that you can "buy" with tokens picked up during play) are very effective. I had to re-play some levels multiple times to get a perfect score. Regarding the infamous Level 11 - I had to come back to it after I'd earned more upgrades. To me, this makes this game a lot of fun, and makes it last a really long time. Stick with it, and with the upgrades you can master all the levels, even on the Hard setting.