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Here are the cheats for Doom 3. You can start using them by pressing Ctrl+Alt+~(Tilde) to bring up the command console
pm_thirdperson 0 3rd Person View OFF
pm_thirdperson 1 3rd Person View ON
give keys All keys
clearlights All lights turn off. Only light is by flashlight….
give all All weapons with full ammo, health and armor
give berserk Berserk mode
give weapon_bfg BFG
give weapon_chaingun Chaingun
give weapon_chainsaw Chainsaw
clear Clear console text
kill Commit suicide
pm_crouchspeed ### Defines how fast you are when you crouch.
pm_runspeed ### Defines how fast you are when you run/sprint.
pm_walkspeed ### Defines how fast you are when you walk.
pm_noclipspeed ### Defines how fast you move with the “noclip” code turned on.
pm_jumpheight ### Defines how high you jump.
com_showfps 1 Draws your Framerate.
freeze Freeze all on screen
benchmark Game Benchmark
give weapon_rocketlauncher give weapon_rocketlauncher
give weapon_flashlight Gives Flashlight
give pda Gives PDAs/disks of the level you’re in.
give armor Gives you 125 armor
god God Mode
set g_dragEntity 1 Grabs objects/bodies when you aim and fire at them
gfxinfo Graphicscard infomation
notarget Invisibility to most enemies
killmoveables Kill all moving enemies
killragdolls Kill all non-moving enemies
killmonsters Kills all Monsters
listmonsters Lists images of monsters
listlightdefs Lists indicated def file settings
give weapon_machinegun Machinegun
testlight Makes a light for you to see better
give ammo Max Ammo
give health Max Health
editor Opens up map editor
give weapon_plasmagun Plasmagun
quit Quit game
Com_Fixedtic -1 Removes 60 FPS Limit
aviDemo Saves a demo of your playing to an AVI movie file
idkfa secret message
say <message> Send message to everyone in multi-player
r_brightness <#> Set brightness level
r_gamma <0-3> Set gamma level
give weapon_shotgun Shotgun
spawn monster_zombie_morgue Spawns a zombie similar to the one in the infirmary.
com_allowconsole 1 This will make it so you only have to press ~ to open the console, no longer alt+ctrl+~.
g_showprojectilepct 1 Toggle hit % to HUD
s_showlevelmeter 1 Toggle sound level display
g_nightmare 1 Unlock Nightmare Mode
noclip Walk through solid objects
g_showplayershadow 1 You can see your shadow during singleplayer.
status Your game status
