Enable all cheats -
Click on the dog tags in the mission room, then type "mia cheats".

Cheat Codes -
Press [F1] at the indicated screen, then enter one of the following codes to
activate the corresponding cheat function:

Result - Screen - Cheat Code
Mission select - Mission room - mia level
All medals - Mission room - mia medal full
Mission completed - While playing a game - mia complete
Invincibility - While playing a game - mia dog