Bugs and comments.
I liked this game alot and i have a bug and ideas for you.
BUG: after I bought everything else I could not buy the final upgrade for rate of fire for the main turret
Ideas:
1. Maybe revamp the art
2. Maybe more turret types (Lightning/Electricity?)
3. After you max out the upgrades on something instead of another price make it say "MAX"
4. If you follow #2 (and maybe #1) maybe make the area larger to accomodate the extra turrets
5. Change the prices and how much you get for killing an enemy and buying upgrades and items. (something more understandable like instead of 1000/10,000 have 100/1000)
Still I like this game alot