They made a major error in this game bieng that after you get hit, you can't consume things but you can get hit again. This makes the game much more tedious because if three things come at you at once all three will hit you because you are too slow to avoid them. Also i was just an asteroid in the last level but i still won.
In the last level you just have to get 4 ion cannons and stockpile money. After that all you do is make a tank, a super soldier and some other backup soldiers :p