Interesting game, although there is a sticky keys bug that ruins it for me. Sometimes, when playing, the Gyrocopter will keep going in whatever direction I last sent it until I re-enter the direction. On hard songs this gets me killed; on easy songs this makes it impossible to work on the "50 kills without being hit" award. Frustrating!
I know many games have a similar bug, caused by internet explorer, however I am not using IE. I'm using Firefox 4.0.1, and this is the only game I've ever had this problem with.
Great game, though there are a couple of ways it could be improved.
One, there's no confirmation dialog when you sell a tower. I've accidentally sold several high level towers when trying to quickly upgrade them in the middle of a wave.
Two, the game really would benefit from hotkeys, especially on spells. It is incredibly frustrating to have 500/500 mana and watch a ninja boss ruin your brilliant score because you can't click meteor fast enough to kill him.
Figured out how to do the last level in 20 seconds. Finished the last level in 15 minutes. Not fun. Lost a star (from 4) due to that, but otherwise good game.
 "Jacob and the Gyrocopter"){kind=icon}
 "Elements of Arkandia"){kind=icon}
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