too many guns...I beat the game using only a Dual machine gun, a couple barrier decoys, and a sniper cannon. And then when I had enough money I bought a damage buffer. Only on the last couple waves of L6 did I need to ditch the Dual machine and get the mini gun.
after 100 tries I got 1800 points, you have to do a handstand the entire time and do a backflip as well. Ride the rocket straight up to the stars and right as you start to fall do the back flip. The real trick is timing the up button on the ramp to get the height.
SPOILER:
To beat the snake, you need to collect 5 fairyflies then activate the teleport thingy. The snake never goes in the same spot twice (with open mouth) so you are always safe going to the spot where it was last.
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