Great Game
This is definitely the most fun I've had in a flash game on Newgrounds in a while. Here are the things I liked about it:
--It was actually rather difficult, even with upgrades
--I liked the upgrades, and how you could....upgrade them :D
--I liked the music
--I liked the look of the game, and the feel of the game
--I liked the achievements
This game is very good, and I hope you continue to make other ones up to this level. Good work!