Start the game with the +set console 1 command line parameter. Press ~ to display the console window, then type cheats on to enable cheat mode. Then, enter one of the following codes in the console window.
*Note: Check below for proper procedure.
Create a Shortcut to the game on your Desktop. Right click on it, go to properties. You will see something like: "C:Games********.exe"
Now type +set console after it: "C:Games********.exe" +set console 1
Code Effect cheats 0 Disable cheats screenshot Screenshot god God mode health (100 or greater) Additional health weapon_give_(1-10) Weapon select massacre Kill all monsters in current level notarget Invisibility noclip No clipping mode cam_toggle Cycle three camera views cam_nextmon Camera focused on next monster cam_nextmon Cycle all characters on level cam_nextsidekic Cycle sidekicks on level k timescale (speed) Change game speed, 1.0 is default map (level name) Level select bind (key and command) Key command binding connect (server) Select active server developer (1 or 0) Toggle game engine messages flushmap (1 or 0) Toggle clean map load with no caching r_speeds (1 or 0) Toggle rendering speed display r_drawflat (1 or 0) Toggle flat-shaded polygons r_fullbright (1 or 0) Toggle lightmaps on surfaces gl_polylines (1 or 0) (server) Toggle line drawing (not available on Voodoo cards)
Thanks to Revolution reader J. R.!