There's a glitch whenever you buy something from the shop. When you buy the level 4 loot, it shifts the cursor to level 4 flag, even if you already have one. Because of this, you can get 4 level 4 flags and a level 3 weapon to max out your ship.
Warning! There is a glitch that makes getting the last badge pretty much impossible. Copypasta this to keep it alive! You CANNOT fully upgrade your towers by using the mouse. You have to use the keyboard keys. Use the TAB button to select the upgrade and use ENTER to take it. WARNING: It will let you spend money on upgrades beyond the max using this trick. So to keep you from losing cash, here are the maxes: ALL range upgrades cap at 2 upgrades, anything more will not be reached Dart Pierce is a single upgrade extra levels do nothing. Cannon bigger explosion is a single upgrade extra levels do nothing. Neither the Boomerang or Super Monkey can go beyond their 1st level upgrades. And last but not least: Tacks can be upgraded all the way to HYPERSONIC. LAST WARNING: Hypersonic on the tack shooters is, imo, TOO fast. I personally feel it makes even hard WAY TOO EASY. Use at your own "risk". If you want a real challenge do it without hypersonic.
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