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Npc metropolice.jpg

<Half-Life 2> npc_metropolice is a point entity available in the Half-Life 2 series. They serve as City 17's primary police force and are one of the most basic Combine enemies.

npc_metropolice uses a small arsenal of weapons and little tactical judgement, designed for the first few levels of Half-Life 2 and its authoritarian atmosphere. npc_combine_s is usually used for the Combine's actual military force.

The gordon_precriminal global state makes all npc_metropolice neutral to the player and citizens, pushing the player away when they get too close and chasing them when provoked. This is used throughout the Half-Life 2 chapter Point Insertion and works best with stunsticks.

In Half-Life 2, they serve as the Combine's thought police, collectively known as Civil Protection, and mainly use stunsticks to brutally police the citizens of City 17. They are the player's main opponent throughout the first few chapters of Half-Life 2, using explosive barrels and mounted guns to their advantage and disadvantage, but they're eventually replaced with npc_combine_s and disappear until the chapter Anticitizen One, where they again function as the main Combine enemies for most of the chapter.

In code, it is represented by class CNPC_MetroPolice, defined in npc_metropolice.h.

Note.png Note: Some keyvalues, flags, inputs, or outputs might not affect an NPC, based on the functionality and coding of the NPC.

Dedicated ConVars

ConVar/CommandParameters or default valueDescriptorEffect
metropolice_chase_use_follow0arbitrary numberCauses pre-criminal npc_metropolice with stunsticks to follow the player indefinitely.
metropolice_move_and_melee1arbitrary numberMakes agitated npc_metropolice activate their stunsticks right as they begin to swing, as opposed to stopping for a moment to activate it once they successfully navigate to their target.
metropolice_charge1arbitrary numberToggles whether npc_metropolice with pistols charge at the player.
sk_metropolice_health40health amountnpc_metropolice health when spawned.
sk_metropolice_simple_health26health amountnpc_metropolice health when the Simple cops flag is checked.
sk_metropolice_stitch_distance1000hammer unitsDistance that npc_metropolice will begin to attempt stitching.
sk_metropolice_stitch_reaction1arbitrary numberMultiplier for the amount of time shots in the stitch line travel from their starting position to the player. Fractions make the npc go through the stitching behavior multiple times, and values above 1 make the stitching slower.
Bug.png Bug: 0 will make the game freeze the moment stitching is attempted.
sk_metropolice_stitch_at_hitcount1arbitrary numberNumber of times a stitching npc_metropolice is allowed to hit a player. Due to random bullet spread, the result may be slightly more or less.
sk_metropolice_stitch_behind_hitcount3arbitrary numberNumber of times a stitching npc_metropolice is allowed to hit a player while behind the player's airboat.[confirm]
sk_metropolice_stitch_tight_hitcount2arbitrary numberNumber of times a stitching npc_metropolice is allowed to hit a player while aiming directly at the player's airboat.[confirm]
sk_metropolice_stitch_along_hitcount2arbitrary numberNumber of times a stitching npc_metropolice is allowed to hit a player while alongside the player's airboat.[confirm]


  •  [1] : Wait Till Seen
Prevents this NPC from seeing (or being seen) until it enters a player's viewcone.
  •  [2] : Gag (No IDLE sounds until angry)
  •  [4] : Fall to ground (unchecked means *teleport* to ground)
  •  [8] : Drop Healthkit
Causes this NPC to drop an item_healthvial upon dying.
  •  [16] : Efficient - Don't acquire enemies or avoid obstacles
  •  [128] : Wait For Script
Forces this NPC to "wait" in an idle state until it finishes playing a scripted_sequence.
  •  [256] : Long Visibility/Shoot
By default, increases a NPC's sight range to 6,000 units and allows it to attack from anywhere within that distance.
Allows this NPC to run its regular AI outside of any player's PVS.
  •  [2048] : Template NPC
Marks this NPC as a template for entities like npc_template_maker. The NPC will not spawn on its own. This is not needed for point_template.
  •  [4096] : Do Alternate collision for this NPC (player avoidance)
Note.png Note: This flag is disabled in episodic for player companions because the StartScripting input does this.
  •  [8192] : Don't drop weapons
  •  [16384] : Ignore player push (in all games since <Source><Source>)
Don't give way to player
  •  [131072] : Simple cops
Sets the NPC's health to the value of sk_metropolice_simple_health instead of sk_metropolice_health and enables more dramatic flinch animations. Used in the early canal levels of the game.
  •  [262144] : Rappel <Obsolete>
Deprecated. Use the "Waiting to rappel" keyvalue instead.
  •  [524288] : Always stitch
This forces the stitching behavior to occur. If the npc_metropolice is armed with an SMG and the player is beneath them, they will shoot a meandering, closing path of bullets (like the first metrocop in d1_canals_07.
  •  [1048576] : No chatter
Automatically gags the NPC and supposedly prevents some metrocop-specific speech that standard gagging doesn't. This is now believed to be non-functional.
  •  [2097152] : Arrest enemies
  •  [4194304] : No far stitching
Stops stitching if the player is over 6000 units away.
Note.png Note: That's about the distance between the two forcefields on the bridge in d2_coast_07.
  •  [8388608] : Prevent manhack toss
Prevents the NPC from deploying their manhack(s). See the EnableManhackToss input.
  •  [16777216] : Allowed to respond to thrown objects
In pre-criminal mode, allows the NPC to chase players who have annoyed them. If this flag isn't enabled, they will call for the nearest available npc_metropolice to chase the agitator. This also occurs if the NPC is using anything other than a stunstick. This does not override the settings of an ai_goal_police.
  •  [33554432] : Mid-range attacks (halfway between normal + long-range)
Extends the NPC's preferred attack distance to 3500 units.


Weapons <choices>
What weapon this NPC should spawn with. Choices are:
  • weapon_pistol
    Note.png Note: With this weapon, npc_metropolice will periodically take a couple steps toward the player if they can path to them.
  • weapon_smg1
  • weapon_stunstick
  • weapon_shotgun
    Warning.png Warning: The default model (police.mdl) doesn't have proper animations for this weapon.
  • Nothing
Number of Manhacks <choices>
Allows a npc_metropolice to carry up to two manhacks on their right shoulder.
Bug.png Bug: If the player gets to about melee distance from a npc_metropolice while they're deploying a manhack, they may be interrupted and the manhack be stuck on their hand until the npc_metropolice dies, after which it will deploy normally.
Pistol starts drawn <boolean>
Whether or not the pistol should start unholstered. The pistol can only be unholstered when the NPC spots an enemy, and inputs like UnholsterWeapon have no effect. This keyvalue has no effect on other weapons.
Bug.png Bug: If the pistol has not yet been drawn and the npc_metropolice must attack during a scripted behavior such as an assault or scripted_sequence, they may skip drawing their weapon and use an invisible gun.


Waiting to Rappel? (waitingtorappel) <boolean>
If yes, this NPC spawns suspended in air and awaits a BeginRappel input. It will then spawn a zipline and slide down. When it hits the ground, NPC will cut away the line and try to move forward a few feet to make room for the next NPC. The NPC will not attempt to clear its landing space if it cannot do so by taking a few steps forward.


Relationship <string> !FGD
<string|targetname or classname> <string|disposition> <int|rank>

Changes whether this NPC likes or dislikes certain others. Used like the ai_relationship entity, with this NPC as the subject. This keyvalue is not included in Valve's FGDs.

Values for disposition are:
  • D_HT: Hate
  • D_FR: Fear
  • D_LI: Like
  • D_NU: Neutral
Target Path Corner (target) <targetname>
The path_corner that this NPC will move to after spawning.
Squad Name (squadname) <string>
NPCs that are in the same squad (i.e. have matching squad names) will share information about enemies, and will take turns attacking and covering each other.
Hint Group (hintgroup) <string>
Hint groups are used by NPCs to restrict their hint-node searching to a subset of the map's hint nodes. Only hint nodes with matching hint group names will be considered by this NPC.
Hint Limit Nav (hintlimiting) <boolean>
Limits NPC to using specified hint group for navigation requests, but does not limit local navigation.
Sleep State (sleepstate) <choices>
Holds the NPC in stasis until specified condition. See also 'Wake Radius' and 'Wake Squad'.
  • 0: None
  • 1: Waiting for threat
  • 2: Waiting for PVS
  • 3: Waiting for input, ignore PVS
  • 4: Auto PVS
  • 5: Auto PVS after PVS
Wake Radius (wakeradius) <float>
Auto-wake if player within this distance
Wake Squad (wakesquad) <boolean>
Wake all of the NPCs squadmates if the NPC is woken
Enemy Filter (enemyfilter) <targetname>
Filter entity to test targets against
Ignore unseen enemies (ignoreunseenenemies) <boolean>
Prefer visible enemies, regardless of distance or relationship priority
Physics Impact Damage Scale (physdamagescale) <float>
Scales damage energy when this character is hit by a physics object. With a value of 0 the NPC will take no damage from physics.


Damage Filter (damagefilter) <targetname>
Name of the filter_damage_type entity that controls which entities can damage us.


Response Contexts (ResponseContext) <string>
Pre-defined response system context{s} for this entity. Format is key:value,key:value,... When this entity speaks, the list of keys & values will be passed to the response rules system.


Disable Shadows (disableshadows) <boolean>
Prevents the entity from creating cheap render-to-texture shadows, or lightmap shadows if the entity is a prop_static. Does not affect shadow mapping.
Disable ShadowDepth (disableshadowdepth) <boolean> (in all games since [Portal 2])
Used to disable rendering into shadow depth (for projected textures) for this entity.
Projected Texture Cache (shadowdepthnocache) <choices> (in all games since [Portal 2])
Used to hint projected texture system whether it is sufficient to cache shadow volume of this entity or to force render it every frame instead.
  • 0 : Default
  • 1 : No cache - render every frame
  • 2 : Cache it - render only once
Disable flashlight (disableflashlight) <boolean> (in all games since [Portal 2])
Used to disable projected texture lighting and shadows on this entity.


Render Mode (rendermode) <choices>
Set a non-standard rendering mode on this entity.

Render FX / Transparency (0 - 255) (renderamt) <integer>
Transparency amount, requires a Render Mode other than Normal. 0 is invisible, 255 is fully visible.
Render Color (R G B) (rendercolor) <color255>
Color tint.
Disable Receiving Shadows (disablereceiveshadows) <boolean>
Prevent the entity from receiving shadows on itself.


Render FX (renderfx) <choices>
Preset pattern of appearance effects.


Pitch Yaw Roll (Y Z X) (angles) <angle>
This entity's orientation in the world. Pitch is rotation around the Y axis, yaw is the rotation around the Z axis, roll is the rotation around the X axis.


Name (targetname) <string>
The targetname that other entities refer to this entity by.
Entity Scripts (vscripts) <scriptlist> (in all games since <Left 4 Dead 2>)
Space delimited list of VScript files (without file extension) that are executed after all entities have spawned. The scripts are all executed in the same script scope, later ones overwriting any identical variables and functions.
Script think function (thinkfunction) <string> (in all games since <Left 4 Dead 2>)
Name of a function in this entity's script which will be called automatically every 100 milliseconds (ten times a second) for the duration of the script. It can be used to create timers or to simulate autonomous behavior. The return value (if present) will set the time until the next call.
Note.png Note: Try to avoid expensive operations in this function, as it may cause performance problems.


Allow Physics Gun (gmod_allowphysgun) <boolean> (only in <Garry's Mod>)
If set, players cannot use Physics Gun on this entity.
Sandbox Tool Whitelist (gmod_allowtools) <string> (only in <Garry's Mod>)
If set, only given tools can be used on this entity. You need to supply the tool class names, the names of the .lua files of those tools. This also includes the context menu properties!


Enables manhack toss (for when it's been disabled by the Prevent manhack toss spawnflag)
SetPoliceGoal <targetname>
Assigns the NPC to an ai_goal_police.
Makes the NPC flick a held weapon_stunstick on.


Start rappelling now.


SetRelationship <string|targetname or classname> <string|disposition> <int|rank>
Changes whether this NPC likes or dislikes certain others. Used like the ai_relationship entity, with this NPC as the subject.
Values for disposition are:
  • D_HT: Hate
  • D_FR: Fear
  • D_LI: Like
  • D_NU: Neutral
SetHealth <integer>
Set the NPC's health.
AddHealth <integer> (in all games since <Half-Life 2: Episode Two><Half-Life 2: Episode Two>)
RemoveHealth <integer> (in all games since <Half-Life 2: Episode Two><Half-Life 2: Episode Two>)
Add to or remove from the NPC's health.
SetBodyGroup <integer>
HACK: Sets this NPC's body group (from 0 - n).
physdamagescale <float>
Scales the damage taken when this character is hit by a physics object. 0 means this feature is disabled for backwards compatibility.
Burst into flames.
IgniteLifetime <float>
Ignite for the given number of seconds.
IgniteNumHitboxFires <integer>
Ignite with the given number of hitbox fires.
IgniteHitboxFireScale <float>
Ignite with the given hitbox fire scale.
Smash into pieces. If this is not possible, disappear.
BecomeRagdoll  (in all games since <Half-Life 2: Episode Two><Half-Life 2: Episode Two>)
Remove itself and instantly become a ragdoll with zero force (just go limp). OnDeath, etc. Outputs will NOT be fired.
Enter/exit scripting state, where NPCs ignore a variety of stimulus that would make them break out of their scripts. They ignore danger sounds, ignore +USE, don't idle speak or respond to other NPC's idle speech, and so on.
SetSquad <string>
Change the name of this NPC's squad. Leaving the parameter blank will remove the NPC from any existing squad.
Wakes up the NPC if it is sleeping.
ForgetEntity <targetname>
Clears out the NPC's knowledge of a named entity.
Gagged NPCs won't speak (or moan, caw, etc.) unless made to be a choreographed scene.
IgnoreDangerSounds <float>
Ignore danger sounds for the specified number of seconds.
HolsterWeapon  (in all games since <Half-Life 2: Episode One><Half-Life 2: Episode One>)
UnholsterWeapon  (in all games since <Half-Life 2: Episode One><Half-Life 2: Episode One>)
Force the NPC to holster or unholster their weapon. Ignored if the NPC is scripting or if the NPC doesn't use weapons.
HolsterAndDestroyWeapon  (in all games since <Half-Life 2: Episode One><Half-Life 2: Episode One>)
Same as HolsterWeapon, except the weapon is destroyed once it has been concealed.
ForceInteractionWithNPC <string> <string>  (in all games since <Half-Life 2: Episode One><Half-Life 2: Episode One>)
Force the NPC to use a dynamic interaction with another NPC. Syntax is <targetname> <dynamic interaction>
UpdateEnemyMemory  (in all games since <Half-Life 2: Episode One><Half-Life 2: Episode One>)
Update (or create) this NPC's memory of of the given entity.
SetMaxLookDistance <float> (only in <Garry's Mod>)
Sets the maximum look distance for the NPC. Defaults are 2048 and 6000 for long range NPCs.


Alpha <integer>
Sets the entity's transparency to a number from 0 (invisible) to 255 (fully visible). Requires the entity to have its Render Mode (rendermode) set to a number other than 0.
Color <color255>
Sets an RGB color for the entity.


SetDamageFilter <string>
Sets the entity to use as damage filter. Pass in an empty string (no parameter) to clear the damage filter.


AddContext <string>
Adds to the entity's list of response contexts. Format is <key>:<value>.
RemoveContext <string>
Remove a context from this entity's list. The name should match the key of an existing context.
Removes all contexts from this entity's list.


Turn dynamic shadows off for this entity.
Turn dynamic shadows on for this entity.
DisableReceivingFlashlight  (in all games since [Portal 2])
This object will not receive light or shadows from projected textures.
EnableReceivingFlashlight  (in all games since [Portal 2])
This object may receive light or shadows from projected textures.


Removes this entity from the world.
Removes this entity and its children from the world.
Note.png Note: Entities already remove orphaned children upon being removed, but this input removes all children on the same frame, being marginally faster than Kill.
AddOutput <string>
Adds a keyvalue/output to this entity. It can be potentially very dangerous, use with care.
KV Format: <key> <value>
I/O Format: <output name> <targetname>:<inputname>:<parameter>:<delay>:<max times to fire, -1 means infinite>
FireUser1 to FireUser4
Fire the OnUser outputs; see User Inputs and Outputs.
Use  !FGD
Same as a player invoking +use; may not do anything depending on the entity. Can also be invoked by firing an output that does not specify an input.
RunScriptFile <script> (in all games since <Left 4 Dead 2>)
Execute a VScript file from disk, without file extension. The script contents are merged with the script scope of the receiving entity.
RunScriptCode <string> (in all games since <Left 4 Dead 2>)
Execute a string of VScript source code in the scope of the entity receiving the input. String quotation may be needed when fired via console.
Bug.png Bug: In <Left 4 Dead 2>, the code is executed in the script scope of the entity that fires the output, not the one receiving the input.
Warning.png Warning: Never try to pass string parameters to a script function with this input. It will corrupt the VMF structure because of the nested quotation marks, which then must be removed manually with a text editor.
CallScriptFunction <string> (in all games since <Left 4 Dead 2>) !FGD
Execute a VScript function in the scope of the receiving entity.
SetLocalOrigin <coordinates> (in all games since <Alien Swarm>) !FGD
Send this entity to a spot in the map. If the entity is parented to something, it will be offset from the parent by this amount.
SetLocalAngles <angles> (in all games since <Alien Swarm>) !FGD
Set this entity's angles.


Fires when this NPC hits the player with a stunstick.
Fired when this NPC is hit by a prop with the targetname cupcop_can.


Fires when done rappelling.


Fired when this NPC takes damage (activator is the damage inflictor)
Fired when this NPC is killed (activator is the killer)
Fired when this NPC reaches half of its maximum health
Fired when this NPC hears a sound (other than combat or the player)
Fired when this NPC hears the player
Fired when this NPC hears combat sounds
OnFoundEnemy <targetname>
Fired when this NPC establishes line of sight to its enemy
Fired when this NPC loses line of sight to its enemy
Fired when this NPC loses its enemy. Usually due to the enemy being killed/removed, or because this NPC has selected a newer, more dangerous enemy
OnFoundPlayer <targetname>
Fired when this NPC establishes line of sight to its enemy, and that enemy is a player
Fired when this NPC loses line of sight to its enemy, and that enemy is a player
Fired when this NPC loses its enemy, and that enemy was a player. Usually due to the enemy being killed/removed, or because this NPC has selected a newer, more dangerous enemy
Fired when this NPC is hurt by a player (activator is the attacker or vehicle driver (if friendly fire))
Fired when this NPC is hurt by a player OR by one of the player's squadmates (activator is the attacker or vehicle driver (if friendly fire))
Fired when this NPC has refused to join the player's squad
Fired when this NPC enters a sleep state
Fired when this NPC comes out of a sleep state
Fired when the NPC starts a forced interaction.
Fired when the NPC aborts a forced interaction for some reason (target NPC died, couldn't be pathed to, etc)
"NPCs in actbusies can no longer perform dynamic interactions." To do: What does this mean?


OnUser1 to OnUser4
These outputs each fire in response to the firing of the like-numbered FireUser1 to FireUser4 Input; see User Inputs and Outputs.
OnKilled  (only in <Left 4 Dead><Left 4 Dead 2>)
This output fires when the entity is killed and removed from the game.