Here is some codes:
To get the goggles you must first get to level 1-4. When you get the tank advance keep going until you find and Destroy the helicopter, without losing the tank. A horn will then go off if done correctly, which is a sign that means you got the goggles.
Unlocking Head Gear.
Unlockable How to Unlock
Blond Hair - Beat the final boss using hard difficulty.
Soviet Union Hat - Get to level 2-1.
Diamond Tierra - Beat Level 2-2 using hard difficulty.
Area 51 Hat - Get to level 3-1.
Private Eye Hat - Beat Level 3-2 using hard difficulty.
Jouster Hat Beat - Level 3-4 using hard difficulty.
Pirate Hat Destroy - the Hairy Nanny Daycare building.
To unlock all minigames, levels and hats, simply set the player 1 name to "ROYGBIV".
Unlock Misc. Hats
To unlock these hats, enter the following names as the player name.
cletus: Unlock Hat #4
april: Unlock Hat #5
superfly: Unlock Hat #7
goodman: Unlock Hat #8
grrl: Unlock Hat #11
abe: Unlock Hat #12
princess: unlocks hat 13
dandy: unlocks hat 14
tomfulp: Unlock Tom Fulp Hair Hat
melty: acid shot powerup
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