Console commands

The console is a feature of many games that can be used to change certain elements of a game. In Left 4 Dead, it can be activated in the Options menu (go to "Keyboard/Mouse", then Enable the "Allow Developer Console" option) and then displayed by pressing the tilde (~) key in game (you don't need to press "Shift"). Valve features a quick-type feature in their consoles that allow rapid entry of commands.

Note that the key used to access the console may be different on non-US keyboard layouts.

'sv_cheats'
The 'sv_cheats' is a prerequisite command to many of the game-altering commands found in Left 4 Dead. By setting sv_cheats to 1, most all commands are then recognized by the game. It is with 'sv_cheats 1' that most of the exploits were found by users in the demo during its pre-order era.

Annotated list of commands
Knowing all the commands isn't quite as good as knowing what they do. The following will describe what each command does and its default value.

Important things to know about your cheat console:
 * Some commands require you to be the game host (such as setting sv_cheats to 1)
 * It is assumed that you have sv_cheats 1 set for the commands described in this section
 * If you turn on cheats then turn them off, many settings get discarded!
 * The console can auto-complete commands, never type more than you need to, just type a few letters then hit the up/down arrows
 * Commands can be chained. Example: sv_cheats 1; z_spawn boomer; z_spawn hunter; z_spawn smoker; z_spawn mob; sv_cheats 0; will toggle cheats on/off and drops a can of whoop ass where you are pointing.
 * You can store your commands in a "myCommands.cfg" file you create in a text editor like "Notepad" (personally I recommend Notepad++ but the XKCD comic reveals the ultimate tool) and put it in C:\Program Files\Steam\steamapps\common\left 4 dead\left4dead\cfg. It will get executed when your server runs. You can also execute a particular config file, e.g., "die.cfg", by using "exec die.cfg" in the console.

Spawn infected
These commands can be used to drop in additional enemies. z_spawn tank z_spawn witch z_spawn boomer z_spawn smoker z_spawn hunter z_spawn common also z_spawn (Unknown)e.g. z_spawn aj will spawn one infected z_spawn mob

Give weapons
Press F10 with sv_cheats 1 enabled

Drops
Need to drop a pipe bomb or molotov instantly, damn the consequences? This will throw an armed pipebomb or molotov at your feet. You might want to be running when you try these.

fire // will drop a molotov in the center of the character lighting you on fire boom // will drop a pipebomb in the center of the character ready to explode

How many zombies would you like, sir?
By default, the game limits how many zombies are drawn at any given time. You can bypass this limit to get truly outrageous numbers of zombies.

z_common_limit 30

Now how can we get the director to give us more mobs of zombies at random times? z_mob_spawn_min_interval_expert 90 z_mob_spawn_max_interval_expert 180 z_mob_spawn_min_size 10 z_mob_spawn_max_size 30

Still not hard enough... perhaps you need a MEGA MOB! z_mega_mob_spawn_min_interval 420 z_mega_mob_spawn_max_interval 900 z_mega_mob_size 50

All good and fine, but what about those spaced out zombies that are just standing still waiting for you to shoot them? Would it not be more awesome if they were always moving and instantly targeted you? z_must_wander 0 z_acquire_far_range 2500 z_acquire_far_time 5 z_acquire_near_range 200 z_acquire_near_time 0 // 0? This can't be right! *Shudder* The master cvar list lies about default values!

Okay, if you got this far, you're going to need more boss zombies. This controls time in seconds between boss spawns and the max number of bosses that can be spawned at any given time: z_special_spawn_interval 45 z_exploding_limit 1 z_gas_limit 1 z_hunter_limit 1 z_minion_limit 3 // This limits the number of 1 type of special infected allowed at one time, In certain cases you would get 3 hunters this will make sure you do not get 4 so in places like Versus you will not be overrun by smokers / hunters / boomers.

That's still not enough zombies? Well then, time to panic (AKA: mega mob on demand)! director_force_panic_event

Oh no, you're still alive? Okay try this: director_panic_forever 1

No more rescues
Don't like the fact that dead isn't dead? Fix it! The variable "rescue_distance" controls how far your teammates must get beyond your dead corpse before you can be rescued. Set to 1 light-year to preclude that ever happening. The second variable, "rescue_min_dead_time", controls how many seconds must elapse after death before you come up for reincarnation. Set to a few centuries (that would be 6294240000 seconds) to preclude that possibility.

rescue_distance 4500 rescue_min_dead_time 60

Bite me
What if infected could kill you with one bite? hunter_pz_claw_dmg 10 z_pounce_damage 5 // There's a delay of 1 second where a teammate can knock it off and you don't take this damage tongue_choke_damage_amount 10 z_hit_from_behind_factor 0 // If a zombie hits you in the back, multiplies the damage done z_witch_damage 100

Environmental and unknown damage modifiers: inferno_damage 40 // Damage per second when getting flamed survivor_extra_damage_ammo_factor 1 // TODO: test this, think it's a multiplier on friendly fire z_gun_damage 10 // TODO: test this, think it controls damage done to zombies per bullet

Walk or sprint?
Don't like the fact that you have a walk key instead of a sprint key? Set this variable to something ludicrous like 5000...

survivor_walk_speed 85

Still not fast enough? Use the following to get in and out of the action at faster than light speeds. REQUIRED: you must be game host

warp_all_survivors_here  // Warp all survivors to the player's cursor warp_all_survivors_to_battlefield // Warp all Survivors to the battlefield warp_all_survivors_to_checkpoint // Warp all Survivors to the exit checkpoint warp_all_survivors_to_finale // Warp all Survivors to the finale radio warp_far_survivor_here // Teleport the farthest away Survivor to your cursor position warp_to_start_area // Warp yourself to a survivor spawn area

Versus Mode for the Man With No Friends
Well, maybe "no friends" is a bit drastic, but this will help you when you NEED some versus and have no one to play with.

sv_cheats 1 sb_all_bot_team 1 director_no_human_zombies 0 chooseteam (or use "M" or whatever key you have assigned to team change) vs_max_team_switches 99

Do note that the computer A.I. players will walk through the stage well enough, but may get hung up when it comes to pushing certain buttons or leaving certain areas. Simply switch teams again, accomplish the goal, and switch back.

Pitch Black Mode
Disable the white background fog, to play the game without the unrealistic lighting effect. This was the original way the game was designed per the dev team: "Left 4 Dead takes place in a variety of dimly lit nighttime environments. Because of this, playtesters weren't able to see zombie silhouettes in the midground and background. Because of this, they were repeatedly getting mobbed. While sudden zombie attacks were inarguably scary, they were also frustrating—players weren't being given the information they needed to react. They wanted that "Here they come!" moment, and we weren't giving it to them. The solution? Light-colored fog.  While not as realistic-looking as actual fog in some settings, it meant playtesters could see attackers in the distance. Once they were able to anticipate attacks, playtesters started to have a much better time."

sv_cheats 1; fog_override 1; fog_enable 0;

Complete list of commands
See: Complete list of console commands