#042 - 714 Box of Shotgun Shells, Chaingun rounds
#035 - 134 Bullets, Shotgun Shells, Armor Shards
#105 - 769 Bullets, Shotgun Shells, Hand Grenades
#407 - 937 Bullets, Shotgun Shells, Small Medikit
#034 - 134 Chaingun rounds, Machine Gun ammo
#029 - 516 Machine Gun ammo, Security Armor
#408 - 937 Shotgun Shells
#116 - 634 Shotgun Shells, Cells
#117 - 634 Shotgun Shells, Chaingun ammo

During gameplay, press CTRL + ALT + ~ to bring up the console. Enter in any of the follow codes to activate their effects.

Code Effect

give keys All keys for the current level
give all All Weapons, Ammo, and Armor
spawn monster_flying_forgotten2 Another "Forgotten" spawn code.
give ammo Fills your ammo to the maximum
give armor Fills your armor points to the maximum
give health Fills your health points to the maximum
noclip fly around and walk through walls
give weapon_shotgun_double Get the new double-barrel shotgun.
give weapon_grabber Get the new grabber gun.
give ammo_grenade_small Gives you Grenades
give weapon_bfg Gives you the BFG 9000
give weapon_chaingun Gives you the Chaingun
give weapon_grabber Gives you the Grabber
give weapon_machinegun Gives you the Machine Gun
give weapon_plasmagun Gives you the Plasma Rifle
give weapon_rocketlauncher Gives you the Rocket Launcher
give weapon_shotgun Gives you the Shotgun
god God Mode (Invincibility)
give PDA PDA Given
map game/marscity1 Play through main game (can give self new weapons, but chainsaw and soulcube are undefined, and Bloodstone doesn't work).
spawn monster_flying_forgotten Spawn a "Forgotten" skull monster.
spawn monster_demon_d3xp_bruiser Spawn a bruiser demon.
spawn monster_zombie_hazmat Spawn a hazmat zombie.
spawn monster_demon_vulgar Spawn a vulgar demon.
spawn monster_hunter_helltime Spawn the first of three hunter demons.
spawn monster_hunter_berzerk Spawn the second of three hunter demons.
spawn monster_hunter_invul Spawn the third and final hunter demon.
map game/deltax Start a new game in Delta Labs - Unknown.
map game/phobos# Start a new game in Phobos Sector # (1 to 4).
map game/erebus# Start a new game on Erebus Level # (1 to 6).
map game/hell Start a new game on the final Hell level.
give weapon_bloodstone_active2 Upgrade Bloodstone to do Hell Time and Berserk.
give weapon_bloodstone_active3 Upgrade Bloodstone to do Hell Time, Berserk, and Invulnerability.
give weapon_bloodstone_active1 Upgrade Bloodstone to do Hell Time.

Unlockables

Nightmare difficulty  -  Harder version of the game in which your health is constantly going down.