Cheat List 
Press CTRL + ALT + ~ to bring up the console. Press is again to get rid of the console. Here you can enter these cheats: 

God Mode: god 
All Weapons, Full Health, Full Armor: give all 
Walk through walls: noclip 
Saves a demo game to an .AVI movie file: aviDemo 
Game Benchmark: benchmark 
Skip to last level: doomhell 
Freeze all on screen: freeze 
Graphics card information: gfxinfo 
Invisibility to most enemies: notarget 
Show FPS: com_drawfps 1 
Acquire all keys: give keys 
Your game status: status 
Quit or Exit: quit 

Weapons 

Machinegun: give weapon_machinegun 
Shotgun: give weapon_shotgun 
Plasmagun: give weapon_plasmagun 
BFG: give weapon_bfg 
Chainsaw: give weapon_chainsaw 
Rocket Launcher: give weapon_rocketlauncher 

Levels 

Mars City 1: marscity1.map 
Mars City Underground: mcunderground.map 
Mars City 2: marscity2.map 
Administration: admin.map 
Alpha Labs Sector 1: alpha1.map 
Alpha Labs Sector 2: alpha2.map 
Alpha Labs Sector 3: alpha3.map 
Alpha Labs Sector 4: alpha4.map 
EnPro Plant: enpro.map 
Communications Transfer: commout.map 
Communications: communications.map 
Monorail Skybridge: recycling1.map 
Recycling Sector 2: recycling2.map 
Monorail: monorail.map 
Delta Labs Level 1: delta1.map 
Delta Labs Level 2A: delta2a.map 
Delta Labs Level 2B: delta2b.map 
Delta Labs Level 3: delta3.map 
Delta Labs Level 4: delta4.map 
Hell: hell.map 
Delta Complex: delta5.map 
CPU Complex: cpu1.map 
Central Processing: cpuboss.map 
Site 3: site3.map 
Caverns Area 1: caverns1.map 
Caverns Area 2: caverns2.map 
Primary Excavation: hellhole.map 
Characters Type ôspawnö and the name of the character to spawn them. 
Flaming Zombie: monster_zombie_bernie 
Chainsaw Zombie: monster_zombie_sawyer 
Z-sec Zombie with machine gun: monster_zombie_zsec_machinegun 
Z-sec Zombie with pistol: monster_zombie_zsec_pistol 
Z-sec Zombie with shield: monster_zombie_zsec_shield 
Z-sec Zombie with shotgun: monster_zombie_zsec_shotgun 
Commando Zombie: monster_zombie_commando 
Commando Zombie with Chaingun: monster_zombie_commando_cgun 
Fat Zombie: monster_zombie_fat2 
Fat Zombie with wrench: monster_zombie_fat_wrench 
Bald Zombie: monster_zombie_maint_bald 
Zombie with no jaw: monster_zombie_maint_nojaw 
Zombie with Wrench: monster_zombie_maint_wrench 
Skinny Zombie: monster_zombie_maint_skinny 
Zombie: monster_zombie_maint 
Zombie: monster_zombie_maint2 
Zombie wth Flashlight: monster_zombie_ maint_flashlight 
Headless Zombie: monster_zombie_suit_neckstump 
Zombie: monster_zombie_suit_bloodymouth 
Skinny Zombie: monster_zombie_suit_skinny 
Zombie in Labcoat: monster_zombie_labcoat 
Zombie Missing Limb: monster_zombie_limb 
Zombie: monster_zombie_skinny 
Zombie with a pipe: monster_zombie_pipe 
Zombie in T-shirt: monster_zombie_tshirt_bald 
Zombie: monster_zombie_tshirt_blown 
Zombie in Jumpsuit: monster_zombie_jumpsuit 
Zombie Eating: monster_zombie_jumpsuit_eating 
Archvile: monster_demon_archvile 
Cherub: monster_demon_cherub 
Hellknight: monster_demon_hellknight 
Imp: monster_demon_imp 
Maggot: monster_demon_maggot 
Mancubus: monster_demon_mancubus 
Pinky: monster_demon_pinky 
Revenant: monster_demon_revenant 
Tick: monster_demon_tick 
Trite: monster_demon_trite 
Wraith: monster_demon_wraith 
Cyberdemon: monster_boss_cyberdemon 
Gaurdian: monster_boss_guardian 
GuardianÆs Seeker: monster_boss_guardian_seeker 
Sabaoth: monster_boss_sabaoth 
Vagary: monster_boss_Vagary 
 

Open the comsole with [Ctrl]+[Alt]+[~] and type in:

 god                            - God mode
 give all                       - All weapons, ammo, shields and health
 give health                    - Health
 give ammo                      - Ammo
 give armor                     - Shields
 give berserk                   - Berserker mode
 notarget                       - Invisibility
 noclip                         - No clipping mode
 com_showFPS 1                  - Show frame rate
 vid_restart                    - Accept video settings without restart
 seta g_nightmare 1             - Nightmare mode
 pm_thirdperson 1               - Third person view

 Weapon cheats:

 give weapons                   - All weapons
 give weapon_flashlight
 give weapon_bfg
 gibe weapon_chaingun
 give weapon_chainsaw
 give weapon_handgrenade
 give weapon_machinegun
 give weapon_pistol
 give weapon_plasmagun
 give weapon_rocketlauncher
 give weapon_shotgun
 give weapon_soulcube

 PDA cheats:

 give pda                       - Get the PDA
 give pda admin_banks           - Get data of the PDA from ...
 give pda admin_dorweiler
 give pda admin_moses
 give pda admin_simons
 give pda alphalabs1_berger
 give pda alphalabs1_krietman
 give pda alphalabs1_lipsitz
 give pda alphalabs1_smith
 give pda alphalabs2_chin
 give pda alphalabs2_connors
 give pda alphalabs3_abrams
 give pda alphalabs3_lamia
 give pda alphalabs3_nelson
 give pda alphalabs3_poota
 give pda alphalabs4_kaczynski
 give pda caverns1_cody
 give pda comm1_blake
 give pda comm1_finch
 give pda comm1_wolfe
 give pda comm1_wolfe
 give pda commoutside_holiday
 give pda commoutside_ridge
 give pda cpu_bates
 give pda cpu_haskell
 give pda cpuboss_tooloose
 give pda delta1_mora
 give pda delta1_price
 give pda delta2a_cinders
 give pda delta2a_raleigh
 give pda delta2a_wilson
 give pda delta2b_bullman
 give pda delta2b_erikson
 give pda delta2b_mcneil
 give pda delta2b_stemmons
 give pda delta3_cerano
 give pda delta3_lee
 give pda delta3_shultz
 give pda delta4_gilbert
 give pda delta5_jackson
 give pda delta5_swann
 give pda enpro_chasar
 give pda enpro_hammer
 give pda enpro_raad
 give pda hell_garlick
 give pda hell_hebert
 give pda marscity2_caseon
 give pda marscity2_duncan
 give pda marscity2_stanton
 give pda marscity2_tyson
 give pda mc1_berneche
 give pda mcunderground_baston
 give pda mcunderground_delahue
 give pda mcunderground_ryan
 give pda mcunderground_young
 give pda monorail_cullen
 give pda monorail_harding
 give pda monorail_hollies
 give pda monorail_ross
 give pda recycling1_garza
 give pda recycling1_sadowayj
 give pda recycling2_johnson
 give pda recycling2_moen
 give pda site3_davis
 give pda site3_rogers
 give video epd                 - Download Video disk with content ...
 give video hydrocon
 give video mfs
 give video bfg
 give video chaingun
 give video demon_museum
 give video ian_report
 give video ipn_news
 give video plasmagun
 give video recycling
 give video soulcube
 give video tablets
 map game/admin                  - Jump to map ...
 map game/alphalabs1
 map game/alphalabs2
 map game/alphalabs3
 map game/alphalabs4
 map game/caverns1
 map game/caverns2
 map game/comm1
 map game/commoutside
 map game/cpu
 map game/cpuboss
 map game/delta1
 map game/delta2a
 map game/delta2b
 map game/delta3
 map game/delta4
 map game/delta5
 map game/enpro
 map game/hell1
 map game/hellhole
 map game/mars_city1
 map game/mars_city2
 map game/mc_underground
 map game/monorail
 map game/recycling1
 map game/recycling2
 map game/site3
 map testmaps/test_box
 map testmaps/test_boxstack
 map testmaps/test_lotsaimps

 There is a way to open the console with the [~] key only: Go to the Data directory
 and generate a file called autoexec.cfg and put in one line:

 seta com_allowConsole "1"

 Save it and now you can open the console with the [~] only.