Gun Metal Cheats

While playing a game, press [F8] to display the chat prompt. Then, type one of the following codes to activate the corresponding cheat function. Note: The codes will not be displayed.
Result
Cheat Code
Invincibility madmax
Full ammo madmechastriesand
Full life madcosmodna
Full shields madducttape
$1,000,000 madmaxamillion
End level madcastlearrgh
Flight mode; A to climb, Z to dive madrubyslippers
Disable flight mode madbananapeel
Turbo mode madbucketoweasels
Disable turbo mode madgetoutandwalk

GESUNDHEIT is the health cheat.

Press [F8] during game play to display the chat
prompt. Then, type one of the following codes to activate the
corresponding cheat function. Note: The codes will not be displayed.

Code
Invincibility madmax
$1,000,000 madmaxamillion
End level madcastlearrgh
Full ammo madmechastriesand
Full life madcosmodna
Full shields madducttape
Flight mode; A to climb, Z to dive
madrubyslippers
Disable flight mode madbananapeel
Turbo mode madbucketoweasels
Disable turbo mode madgetoutandwalk
Trainer: All missions and weapons unlocked by PiZZA
Trainer: +2 by iMSDOX

MADMECHASTREISAND - Full Ammo
MADCOSMODNA - Full Life
MADDUCTTAPE - Full Shields
MADRUBYSLIPPERS - Flight Mode (A,Z)
MADBANANAPEEL - Disable Flight Mode
MADBUCKETOWEASELS - Turbo Mode
MADGETOUTANDWALK - Disable Turbo Mode
MADMAXAMILLION - Get $1 Million
MADCASTLEARRGH - End Level