secert is to keep it on normal and on 2 entrance. Disable all weapons but pellet gun. Keep upgrade buy sell unlimited and normal waves. Build maze and lots just keep upgrading to sniper rifle
Congratulations! You just won the Around the World in 18 Days Badge and 30 points!
Game cleared (ve taken longer than the alotted time, you can refresh and clear your progress from the title screen.
First thing I did was make sure I made 17 off day 1 by skipping across. Then acceleration. On day 2 you can break distant achievment and then buy glider #1. After that focus on breaking an achievment a day and dont go back to another day until you are sure you can break remaining achievments. I had everything maxed on day 18 except ramp height. Always try for height achievment and glide time achievment. Break speed and distance achievment after those 2 and you will have plenty for upgrades
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