To active cheats, in the main menu, hold down the shift key and type:
"MENSAAAA"
You'll hear a guy say "thats what I need." After that during the game
you can type the following cheats:
LShift+LCTRL+A = skip level
LShift+LCTRL+R = restart level
LShift+LCTRL+C = continue if mission failed
Press G = god mode
Also, enter Neon's profile in the characters menu and type in the code
"ZIOCLETO", once you reach a mission with neon, you will play the mission
with his skeleton.