Codes:
While playing a game, press T to enter the "Talk" function, then enter one of the following codes:

Cheat Code - Result

     mpgod - God mode 
     mpkfa - Full ammo, armor, and health 
     mphealth - Full health 
     mpammo - Full ammo 
     mparmor - Full armor 
     mpclip - Toggle clipping 
     mppos - Toggle coordinate display 
     mpcamera - Adjust camera 
     mplightscape - Adjust lighting 
     world [name] - Level select [Note] 

Note: Select a name from the level name list below.
Level names:

     01_Ambush 
     02_Quarters 
     03_MCA_Dock 
     04_Shuttlebay 
     05_LZ_Minotaur 
     06_Entrance 
     07_Avernus1 
     08_Airshafts 
     09_Comm1 
     10_Comm2 
     12_Comm3 
     13_New_MCA 
     14_Maritropa1 
     15_Depot 
     16_Slums 
     17_Lost_Cat 
     18_Slums 
     19_Rendezvous 
     20_Maritropa1 
     21_Maritropa2 
     22_Tram 
     24_CMC_Sec1 
     25_CMC_Sec2 
     26_Tram 
     27_New_MCA 
     28_Airshipdock 
     29_Airship 
     30_Research 
     31_Avernus1 
     32_Museum 
     33_Quarters 
     34_Energy_Plant 
     34_Spires 
     35_Command 
     35_Fortress 
     36_Elevator 
     36_Kato_Center 
     37_Gabriel