At the Steam control panel, Right Click the "Left 4 Dead 2" option, and select "Properties" under the "My Games" tab. In the General tab, select "Set Launch Options", enter "-console" in that field, and accept it. Start the game, and the console window should appear at the main menu. Enter "bind p toggleconsole" as a console command. Then, type one of the following "map [map name]" codes and press [Enter] to load the corresponding map. Note: The same entries can be used with the "changelevel [map name]" or "changelevel [map name]" codes during the game.
Alternately, at the main menu, select "Options", then choose the "Keyboard/Mouse" selection. Enable the "Allow Developers Console" option. Press ~ to display the console window. Enter "bind p toggleconsole" as a console command. Then, type one of the following "map [map name]" codes and press [Enter] to load the corresponding map:
Dead Center
Dark Carnival
Swamp Fever
Hard Rain
The Parish
While playing the game, press P or ~ to display the console window. Enter "sv_cheats 1" to enable cheat mode. If you entered the code correctly, the message "Server cvar 'sv_cheats' changed to 1" will appear. You can now enter one of the following codes to activate the corresponding cheat function. Note: Enabling cheat codes will disable achievements from being earned.
| Result | Cheat Code |
| Toggle God mode for entire team | god [0 or 1] |
| Gain health | give health |
| Defibrillator | give defibrilator |
| Adrenaline | give adrenaline |
| First aid kit | give first_aid_kit |
| Pain Pills | give pain_pills |
| Toggle no clipping mode | noclip |
| Toggle Incendiary Ammo upgrade | upgrade_add incendiary_ammo |
| Toggle Explosive Ammo upgrade | upgrade_add explosive_ammo |
| Toggle Laser Sight upgrade | upgrade_add laser_sight |
| Toggle infinite ammunition | sv_infinite_ammo [0 or 1] |
| Refill ammunition | give ammo |
| Double pistol | give pistol |
| Magnum | give pistol_magnum |
| Auto shotgun | give autoshotgun |
| Chrome shotgun | give shotgun_chrome |
| Pump shotgun | give pumpshotgun |
| SPAS shotgun | give shotgun_spas |
| SMG | give smg |
| Silenced SMG | give smg_silenced |
| AK-47 | give rifle_ak47 |
| M16 | give rifle |
| Combat rifle | give rifle_desert |
| Hunting rifle | give hunting_rifle |
| Sniper rifle | give sniper_military |
| Grenade launcher | give weapon_grenade_launcher |
| Hunter claws | give melee |
| Boomer Bile | give vomitjar |
| Frying pan | give frying_pan |
| Guitar | give electric_guitar |
| Machete | give machete |
| Nightstick | give tonfa |
| Molotov cocktail | give molotov |
| Pipe bomb | give pipe_bomb |
| Propane tank | give propanetank |
| Gas can | give gascan |
| Oxygen tank | give oxygentank |
| Spawn Spitter | z_spawn spitter |
| Spawn Jockey | z_spawn jockey |
| Spawn Charger | z_spawn charger |
| Spawn common zombie | z_spawn zombie |
| Spawn zombie mob | z_spawn mob |
| Spawn Boomer | z_spawn boomer |
| Spawn Hunter | z_spawn hunter |
| Spawn Witch | z_spawn witch |
| Spawn Smoker | z_spawn smoker |
| Spawn Tank | z_spawn tank |
| Level select | map [map name] |
| Level select | changelevel [map name] |
| Disable all cheats | sv_cheats 0 |
| Commit suicide | kill |
| Quit game | quit |
At the Steam control panel, Right Click the "Left 4 Dead 2 Demo" option, and select "Properties" under the "My Games" tab. In the General tab, select "Set Launch Options", enter "-console" in that field, and accept it. Start the game, and the console window should appear at the main menu. Enter "bind p toggleconsole" as a console command. Close the console window, and start a single player game. While playing the game, press P to display the console window, then enter "sv_cheats 1" to enable cheat mode. If the message "Can't use cheats now; please exit to main menu and start your own server with "map mapname" so that you can enable cheats." appears, enable the "map c5m1_waterfront" or "map c5m2_park" code. You will return to the main menu. Enable either "map" code again, then enable the "sv_cheats 1" code again. Then, type one of the following codes and press [Enter] to activate the corresponding cheat function:
| Result | Cheat Code |
| Toggle God mode for entire team | god [0 or 1] |
| Gain health | give health |
| Defibrillator | give defibrilator |
| Adrenaline | give adrenaline |
| First aid kit | give first_aid_kit |
| Pain Pills | give pain_pills |
| Toggle no clipping mode | noclip |
| Toggle Incendiary Ammo upgrade | upgrade_add incendiary_ammo |
| Toggle Explosive Ammo upgrade | upgrade_add explosive_ammo |
| Toggle Laser Sight upgrade | upgrade_add laser_sight |
| Toggle infinite ammunition | sv_infinite_ammo [0 or 1] |
| Refill ammunition | give ammo |
| Double pistol | give pistol |
| Magnum | give pistol_magnum |
| Auto shotgun | give autoshotgun |
| Chrome shotgun | give shotgun_chrome |
| Pump shotgun | give pumpshotgun |
| SPAS shotgun | give shotgun_spas |
| SMG | give smg |
| Silenced SMG | give smg_silenced |
| AK-47 | give rifle_ak47 |
| M16 | give rifle |
| Combat rifle | give rifle_desert |
| Hunting rifle | give hunting_rifle |
| Sniper rifle | give sniper_military |
| Grenade launcher | give weapon_grenade_launcher |
| Hunter claws | give melee |
| Boomer Bile | give vomitjar |
| Frying pan | give frying_pan |
| Guitar | give electric_guitar |
| Machete | give machete |
| Nightstick | give tonfa |
| Molotov cocktail | give molotov |
| Pipe bomb | give pipe_bomb |
| Propane tank | give propanetank |
| Gas can | give gascan |
| Oxygen tank | give oxygentank |
| Spawn Spitter | z_spawn spitter |
| Spawn Jockey | z_spawn jockey |
| Spawn Charger | z_spawn charger |
| Spawn common zombie | z_spawn zombie |
| Spawn zombie mob | z_spawn mob |
| Spawn Boomer | z_spawn boomer |
| Spawn Hunter | z_spawn hunter |
| Spawn Witch | z_spawn witch |
| Spawn Smoker | z_spawn smoker |
| Spawn Tank | z_spawn tank |
| Commit suicide | kill |
| Quit game | quit |
Use an adrenaline shot, then use your medikit to heal. This takes a much less time, especially when you are dealing with a horde.
Find a corner, and have a melee weapon equipped. Hold [Melee] while aiming at the approaching zombies. Note: You may get hit a few times.
In the bar in the abandoned town, find the jukebox, and play it to hear "Eat Your Brains" by Jonathan Coulton.
In Dark Carnival: Level 4, find the strength-testing mini-game in the first area. Inject adrenaline, and hit it with a melee weapon to get the "Gong Show" achievement.
In Dark Carnival: Level 2, find the shooting range. Score over 500 points to make a garden gnome appear. Carry the gnome to the end of the level, and board the chopper with it at the end of Dark Carnival: Level 5 to get the "Guardin' Gnome" achievement.
In Dark Carnival: Level 4, find the Whack-A-Mole mini-game. Get a score of 42 to get the "Stache Whacker" achievement.
In The Parish: Level 3, when you reach the impound lot area with all the cars, just use a melee weapon to kill the Infected. The computer players will not set off an alarm. All the red cars have car alarms, so try to stay by the white cars. Once you make it past the area with all the cars without setting off an alarm, you will get the "Violence In Silence" achievement once you make it to the safe house.
Note: All three other players must be bots for this trick to work. Before the alarm goes off, clear all explosive items and do not use incendiary ammo. Then, crouch in the corner near the entrance to the plane so the Infected cannot get you from behind or either side. Once the alarm is sounded and the horde start attacking, throw a Molotov to block the entrance. After that, the computer players should stand in front of you and take the damage. Just stay in the same place the entire time, and you should get the "Wing And A Prayer" achievement.
Successfully complete the indicated task to unlock the corresponding achievement. To view your achievements and stats in Steam, select "Community", "My profile", "View all my games", then the game and view stats.