This is my strat for beating the game.
1. at first just do your normal upgrade stuff until you get past the spikes.
2. after you get past save up 20 coins(unless you already have 20) and buy the multiplier
3. keep on collecting coins while you keep on upgrading your multipler
4. once your multiplier is fully upgraded go for the laser (if you cant reach it before you die upgrade your normal stuff)
5. once you have the laser upgrade its power until its max
6. then focus on ammo(with full power it only takes 4 shots to kill the boss so upgrade until you have as much as you feel you need)
7. do any normal upgrades you might want before the end
8. go fight the boss. dodge his fire until he starts moving back and forth firing down. when he does this stand under him to avoid damage. run away once he stops. he will fall to the ground. when he does this shoot him. repeat this until u win.
Hope this helps anybody whose stuck!
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