To enable cheat mode, start the game with the following parameters:
+set ui_console 1 +set cheats 1 +set thereisnomonkey 1
Then, while in the single-player game, press "~" to bring up the console and type any of the codes listed below:
dog - God Mode
fullheal - Full Health
wuss - All Weapons & Ammo
noclip - No Clipping (Go Through Walls)
notarget - Show Game Version
NOTE: To start the game with those parameters, you must modify the shortcut for the game by right clicking on the shortcut and selecting properties. Then, change the TARGET box to add in the command-line cheat. Simply add the "+set ui_console 1 +set cheats 1 +set thereisnomonkey 1" to the end of where your shortcut points to.
Example:
C:mohdemoMOHAADemo.exe +set ui_console 1 +set cheats 1 +set thereisnomonkey 1
If your target contains quotations, you must put the parameter OUTSIDE of the quotations.
Example:
"C:moh demoMOHAADemo.exe" +set ui_console 1 +set cheats 1 +set thereisnomonkey 1