Just make a line of buzzsaws so they are touching so the turtles can't slip through, but leave a hole so they can get up there. then max the floor with launcers and throw in some mines for fun. its pretty much impossible to lose
To get a BUNCH of upgrade points pretty quickly try this strategy:
Work your way to level 9. On this level use your rockets. Upgrade your rockets all the way. Then upgrade your speed to about level 3. (Its easier with higher levels of speed, but ive done this with lvl. 3 speed) Then let your rockets do there work and you should have very minimal bullets to dodge. Avoid the bullets by lazily moving side to side and adjusting slightly when necessary. When you get to the end move to the left, then when the divers come done quickly move to the right then up and around to dodge their attack. If you did this correctly you should have between 60,000 and 67,000 upgrade points. If you do it without getting hit (which is pretty easy if you pay attention) your upgrade points are doubled and you can rack up 120,000 - 135,000 upgrade points in about 20 seconds of level.
Multiplayer or PvP would be great. Also, explanations of all the numbers on the cards would be good. Needs more bosses to beat, the ones are fairly easy. I beat the game in about 45 mins.
VERY boring game. needs upgrades for ship. "dice" looking things need to tell you what they do. needs music. needs harder/more enemies hit 100,000+ without any difficulty. just a waste of an hour
46 fully upgraded missle towers, 18000000000 dollars, and level 396. and still no enemy gets past the first stretch. so easy. needs speed up and send next wave button