You don't need to pay to play. You only need to pay if you are impatient. Just go outside, enjoy life for two hours. Or even get some other badges. Then come back and now you have full energy.
Hard badge got first try, 5080029. 85% collected. Floral shapes, wave, straight. Just go left to right up near the top, but low enough so you can see reds coming. Try to get every yellow and avoid every red.
Got the hard badge first try. Strafing (hold mouse button) is very useful. Go berserk (double click) whenever you are in trouble. Bullet time (Space) if berserk isn't ready yet and you are in trouble. Have full upgrades. Don't try to collect money.
If you keep upgrading the tack tower's firing rate using lajekahr's method, it will get to "hypersonic" and destroy everything except lead balloons. Nothing can get past a bomb tower plus that
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