Difference between revisions of "Sentry Gun"

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{{Featured article tag}}
 
{{Featured article tag}}
[[Image:Engywithsg.png|right|350px|The Engineer with a Level 3 Sentry]]
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[[File:Engywithsg.png|right|350px|The Engineer with a Level 3 Sentry]]
{{Quotation|'''The Engineer'''|How am I going to stop some big mean mother hubbard from tearing me a structurally superfluous new behind? The answer: use a gun. And if that don't work... use '''more''' gun.}}
 
The '''Sentry Gun''' (sometimes known as a "'''Sentry'''", "'''Turret'''",  or abbreviated to "'''SG'''") is a [[building]] that can be constructed by an [[Engineer]] and functions as an automated turret which fires upon any enemy who walks into its line of sight. The Sentry Gun will always target and fire on the closest enemy player or building, provided they are within firing range and in line of sight of the Sentry Gun (not behind a wall, etc).
 
  
The Sentry Gun costs 130 [[Metal]] to build, 200 Metal to upgrade to level two, and an additional 200 to upgrade to the third and final level. With each upgrade level the Sentry Gun becomes more powerful, gaining machine guns, rockets and the ability to take more damage. The firing range remains constant regardless of level.  
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{{Quotation|'''The Engineer''' ([[Meet the Engineer]])|How am I going to stop some big mean mother hubbard from tearing me a structurally superfluous new behind? The answer: use a gun. And if that don't work... use '''more''' gun.|sound=Engineer moregun.mp3}}
  
The Sentry Gun's ammo may be replenished with your own metal by hitting it with your [[Wrench]]. Each bullet reloaded costs 1 metal and each rocket reloaded costs 2 metal.
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The '''Sentry Gun''' (abbreviated to '''SG'''), officially known as '''Sentry Mechanical Firing Device''' and also known as '''Sentry''' or '''Turret''', is a [[Buildings|building]] that can be constructed by the [[Engineer]] using the [[PDA]], the Engineer's build tool. The gun itself is a tripodal device constructed of metal, team-colored paint, and a laser sight (when used with the [[Wrangler]]).
  
When placing a Sentry Gun, the limit of its range is represented by a 3D sphere of your team color, with a radius of 1100 [[Hammer unit]]s. A Sentry Gun that is being constructed will have its [[health]] increase gradually until it reaches its maximum health upon completion. The Sentry Gun rotates 90 degrees to patrol the area, but is capable of rotating 360 degrees to lock on to a target. This takes a brief moment however, which may allow faster foes to slip past its range. The Sentry Gun can also be manually rotated to face a different direction before you build it: When the blueprint is shown, using the alternate fire button ([[default key]]: MOUSE2) will rotate the blueprints counter-clockwise by 90 degrees.
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A level one Sentry Gun is a single-barrel machine gun with an internal magazine. The Sentry has a motion sensor, as stated in Meet the Engineer and the [https://cdn.akamai.steamstatic.com/steam/apps/440/manuals/SentryManual_web.pdf Sentry Manual].
  
Sentry Guns will not fire upon enemy [[Spy|Spies]] that are [[cloaked]] or [[disguise]]d. Sentry Guns will also not fire upon enemies in its range if the enemy is behind cover - this cover includes the Engineer's [[Dispenser]]. Sentry Guns are also unable to fire if an enemy Spy attaches an [[Electro Sapper]] to it or while they are being upgraded/built. A destroyed Sentry Gun leaves 60 Metal worth of pieces, which can also be picked up by other classes as [[Ammo]].
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A level two Sentry Gun appears to use an automatic cranking system to rotate the barrel, as indicated by the 2 electric cables visible. It also has 2 Gatling guns and a laser sight is built into the carbine body. Its ammunition is belt-fed.
  
Unlike most other weapons, the Sentry Gun's weapons do not get affected with damage falloff from range nor can it gain [[critical]]s. It is possible however, to make the Sentry Gun deal [[Critical Hit|Mini-Crit]] attacks and damage if its target is coated in [[Jarate]] or if the Engineer who built the Sentry Gun is close to a Soldier with an active [[Buff Banner]], boosting the damage of each bullet to 22.
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A level three Sentry Gun is identical to the level two, with the exception of an additional set of rocket silos on the top, which comes out of the back ammunition housing area.
  
Also included in the [[Engineer Update]] is an unlockable [[Pistol]] replacement, [[Wrangler|The Wrangler]], which allows the Engineer to take direct control of his Sentry Gun by 'marking' targets manually. Doing so shuts down the Sentry Gun's automated target-lock system, but diverts the excess power from the targeting system into speeding up its firing rate, effectively doubling the damage-per-second of the Sentry Gun. Also, the Wrangler provides the Sentry Gun with a protective shield which absorbs two-thirds of enemy fire while the Wrangler is active. Once the Engineer switches away from the Wrangler, however, his Sentry Gun is left defenseless for 3 seconds while its auto-lock targeting computer reboots.
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The Sentry Gun functions as an automated turret that fires at the closest enemy within its range and line of sight. Dealing constant as well as consistent damage with noticeable [[knockback]] and having an immunity to [[Critical hits]], a Sentry Gun is the cornerstone of a successful defensive setup. On the other hand, they take a while to set up to full potential, and even a fully stocked Sentry Gun can be destroyed with little trouble by a well-executed [[ÜberCharge]] or a [[Spy]] with his [[Sapper]]. Engineers must be on the lookout for such threats to ensure their Sentry Gun's survival. If a Sentry Gun is sapped, it gains a 33% damage resistance against a Spy's weapons.
  
[[Image:Killicon tool chest.png|thumb|right|Icon for a hauled item being destroyed via the Engineer's death.]]
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== Functionality ==
Since the [[Engineer Update]], players are able to pick up and move their buildings around. An Engineer carrying his Sentry Gun moves 25% slower and cannot fire or change weapons. However, a redeployed Sentry Gun retains its previous level and automatically sets up twice as fast. Engineers do not lose any ammo or metal by moving Sentry Guns. If the Engineer is killed while hauling his Sentry Gun it is automatically destroyed along with him, giving a notification in the kill icon area of the screen. Sentry Guns under the effects of an [[Electro Sapper]] cannot be picked up.  
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=== General ===
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The Sentry Gun costs 130 [[Metal]] to build, 200 Metal to upgrade to Level 2, and an additional 200 to upgrade to the third and final level totaling to 530 Metal. With each upgrade level, the Sentry Gun becomes more powerful, gaining machine guns, rockets, as well as more health and a minor damage resistance to all Miniguns. The firing range remains constant regardless of level. The Sentry Gun's [[ammo]] and [[health]] may be replenished with Metal by the Engineer hitting it with his [[Weapons#engiemelee|melee weapon]]. Each bullet reloaded costs 1 Metal and each rocket reloaded costs 2 Metal.
  
If a Soldier has The [[Tank Buster]] Pack equipped, he will receive 20% less damage from any level of Sentry Gun.
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When placing a Sentry Gun, the Engineer can see the limit of its range represented by a team-colored sphere of 1100 [[Hammer unit]] radius. A Sentry Gun that is being constructed has health increase gradually until it reaches its maximum health upon completion. While automatically scanning, the Sentry Gun rotates 90 degrees about the direction it is pointing; however, it is capable of detecting and rotating the full 360 degrees to lock on to a target. This takes a brief moment, however, which may allow faster foes to slip past its range. The Sentry Gun can also be manually rotated when placing to face a different direction before building commences. When the blueprint is shown, using the alt-fire button ([[List of default keys|default key]]: {{Key|MOUSE2}}) rotates the blueprints counterclockwise by 90 degrees.
  
A [[Pyro]] can [[Compression Blast|reflect]] the rockets of an enemy level 3 Sentry Gun.
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=== Properties ===
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As do other Buildings, Sentry Guns emit sound cues to alert players to their presence and status. A scanning Sentry Gun makes a number of beeps every time it reverses its rotation ([[Media:Sentry scan.wav|1]], [[Media:Sentry scan2.wav|2]] [[Media:Sentry scan3.wav|3]]) — the number of beeps corresponds to its upgrade level, where a Level 3 turret makes three quick beeps. Additionally, this beeping increases somewhat in volume with Level 2 then Level 3 Sentry Gun's level; so, the higher the level, the farther away the Sentry Gun can be heard; this fact can help attentive players find guarded areas. The Sentry Gun's scanning noise sounds slightly different when being fired on by the enemy; slight clicks can be heard along with the regular beeps. The scanning Sentry Gun also makes a [[Media:Sentry spot.wav|distinctive noise]] when it detects and locks onto an enemy target just before firing — this noise both alerts the enemy of the detection by the Sentry Gun and the team of the presence of an enemy within the range of the Sentry Gun. Enemies detected by a Sentry Gun hear its noise as a [[Media:Sentry spot client.wav|slightly different alert noise]]. All of these scanning noises are silenced when a Sentry Gun is [[Wrangler|Wrangled]].
  
== Combat Mini-Sentry Gun ==
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A Sentry Gun constantly checks if there is an enemy player or building in scanning range with a clear line of sight. If multiple targets meet this criteria, it selects the closest one and switches targets the instant another target is closer, prioritizing players over buildings in its range. Sentry Guns also only attempt to fire once they have lined up with the target, even if firing before then could cause damage to an enemy. Sentry Guns have a maximum rotation and pitching speed when attempting to track a target, which increases with level and is faster than its idle scanning rotation. Sentry Guns still aim and try to fire at enemies even if their ammo reserves are empty.
[[Image:Engineer Update MiniSentries.png|right|350px|The Combat Mini-Sentries as seen on the [[Engineer Update]] page.]]
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{{Quotation|'''The Heavy''' on the Engineer's strategies''|Go ahead! Build your tiny gun! Then '''RUN'''!|sound=Heavy_taunts17.wav}}
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Sentry Guns cannot see through geometry and Engineer buildings; however, they ignore friendly players.
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After running out of valid targets for whatever reason, the Sentry Gun briefly stays pointing in the direction of its last detected target before returning to its scanning sweeps.
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Since the [[Engineer Update]], players are able to [[haul]] their buildings around. An Engineer carrying his Sentry Gun moves 10% slower and cannot fire or change weapons. A redeployed Sentry Gun retains its previous level and automatically sets up twice as fast. Engineers do not lose any Ammo or Metal by moving Sentry Guns (unless the Sentry Gun was picked up with the [[Rescue Ranger]]'s alt-fire, which costs 100 metal for moving any building). If the Engineer is killed while hauling his Sentry Gun, it is automatically destroyed along with him and gives a notification in the kill icon area of the screen. Sentry Guns under the effects of a [[Sapper]] cannot be picked up.
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Like most other weapons, the Sentry Gun's weapons have [[Damage#Distance modifier|damage ramp-up and fall-off]]. Sentry Gun bullet ramp-up and fall-off is calculated based on the distance between the enemy and the Sentry Gun. However, the rockets from a Level 3 Sentry Gun calculate their ramp-up and fall-off based on the distance between the enemy and the Engineer who built the Sentry Gun.
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Unlike most other weapons, the Sentry Gun's weapons do not gain [[Critical hits]]. It is possible, however, to make the Sentry Gun deal [[Critical hits#Mini-crits|Mini-Crit]] attacks and damage if its target is coated in [[Jarate]], being [[Mechanics#MarkedForDeath|Marked For Death]], or if the Engineer who built the Sentry Gun is close to a Soldier with an active [[Buff Banner]] – boosting the damage of each bullet to 22.
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 +
Sentry Guns are controlled by the ''TF2'' server rather than the Engineer's client. That means Sentry Guns behave the same regardless of the connection quality of the Engineer that built them.
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 +
==== Specific properties ====
 +
Included in the [[Engineer Update]] as an unlockable secondary replacement, the [[Wrangler]] allows the Engineer to take direct control of his Sentry Gun by "marking" targets manually. Doing so shuts down the Sentry Gun's automated target-lock system but diverts the excess power from the targeting system into speeding up its firing rate, effectively doubling the damage-per-second of the Sentry Gun. The Wrangler also provides the Sentry Gun with a protective shield which absorbs two-thirds of enemy fire while the Wrangler is active. A wrangled Sentry Gun has no maximum range, though its accuracy slightly decreases at longer ranges and its knockback force is halved against targets outside of its normal reach. Once the Engineer switches away from the Wrangler, however, his Sentry Gun is unable to fire for 3 seconds while its auto-lock targeting computer reboots. It is still shielded during this time.
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In [[Mann vs. Machine]], Sentry Guns can gain benefits from certain [[Power Up Canteen]]s. An ÜberCharge Canteen forms a Wrangler-esque shield around the Sentry Gun, reducing incoming damage by 90%. Use of a Kritz Canteen triples the Sentry Gun's firing rate. An Upgrade Buildings Canteen instantly upgrades the Sentry to Level 3 as well as fully repair it, however it does not refill the Sentry Gun's ammo. Sentry Guns can also be upgraded at [[Upgrade Station]]s to increase their health and firing rate, and the Engineer can even buy a [[#Disposable Mini-Sentry|Disposable Sentry Gun]], allowing him to place a second Mini-Sentry that is slightly worse than a [[#Combat Mini-Sentry Gun|Combat Mini-Sentry]].
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=== Vulnerabilities ===
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Sentry Guns are damaged by most weapon effects that damage players; however, some effects are modified for Sentry Guns. Also, weapon damage done to a Sentry Gun does not suffer from [[Damage#Distance and randomness modifier|range falloff]], with the exception of any scatter-based weapons or indirect explosions. A destroyed Sentry Gun drops 65 Metal worth of scrap pieces, which can also be picked up by other classes as Ammo.
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Sentry Guns do not fire upon enemy [[Spy|Spies]] that are [[cloak]]ed. In general, Sentry Guns do not fire upon enemy Spies that are [[disguise]]d; however, if the Sentry was firing upon the Spy at the time the disguise was activated, it continues to fire upon the Spy until the Spy cloaks, breaks line of sight, or moves out of range. Sentry Guns also do not fire upon enemies in its range if there is a water surface between them or if the enemy is behind cover – this cover includes the Engineer's [[Dispenser]]. Sentry Guns are also unable to fire if an enemy Spy attaches a [[Sapper]] to it or while they are being upgraded/built. Feign deaths produced by the [[Dead Ringer]] are not added to the Sentry Gun kill/assist counter but do contribute to the [[Engineer achievements|Best Little Slaughterhouse in Texas]] achievement.
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 +
An Engineer is vulnerable to damage from his own Sentry Gun's bullets. For about the first 300 [[Hammer unit]]s of their flight, Sentry Gun rockets pass through the Sentry Gun's Engineer without detonating as if he were another member of the same team. However, if the rockets do strike another surface within this distance and explode, the Engineer is vulnerable to the resulting [[Projectiles#Explosions|splash damage]]. Beyond this initial distance, the Engineer is fully vulnerable to his own Sentry Gun's rockets (the [[knockback]] from Sentry Gun self-damage enables the Engineer to perform [[Jumps#Sentry bullet jump|bullet]] and [[Jumps#Sentry rocket jump|Sentry rocket jumps]], especially with the aid of the Wrangler).
  
The Combat Mini-Sentry Gun is a more combat-efficient version of the standard Sentry Gun, and is a component of the [[Engineer]]'s [[Gunslinger]] unlock. The Combat Mini-Sentry Gun has several advantages: it costs only 100 [[metal]] to place, constructs at four times the speed of the original Sentry Gun, is deployed at full health and fires 50% faster than a Level 1 Sentry Gun.  However, it is neither repairable nor upgradable, as it is intended for short-term use rather than long-term area denial fortification. It also deals only 50% the damage per shot of the original Level 1 Sentry Gun. Combat Mini-Sentry Guns can be picked up and redeployed like regular Sentry Guns.
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=== Metal spending priority ===
 +
When an Engineer hits a Sentry Gun with their melee weapon, the metal is spent in a certain order:
  
{{clr}}
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# Health
 +
# Upgrade Progress
 +
# Ammo
 +
## Bullets
 +
## Rockets
  
==Sentry Gun Levels==
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However, ammo is usually filled alongside Health and the Sentry Gun's Upgrade Progress. Bullet ammo is refilled first, followed by rocket ammo.<ref>[https://www.youtube.com/watch?v=_Y5ywUe8678 Uncle Dane - Engineer Rules]</ref>
  
[[File:Sentryani.gif|right]]
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{{Weapon Demonstration}}
{| class="wikitable grid"
 
! class="header" | Level
 
! class="header" | Kill Icon
 
! class="header" | Health
 
! class="header" | Cost
 
! class="header" | Weaponry
 
! class="header" | Damage
 
! class="header" | Ammo
 
|-
 
| height=150 |
 
  
{| class="wikitable grid"
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== Combat Mini-Sentry Gun ==
|'''1'''
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[[File:Engineer Update MiniSentries.png|right|350px|The Combat Mini-Sentries as seen on the [[Engineer Update]] page.]]
|}
 
[[Image:Lvl1sentry.png|100px]]
 
|{{Icon killicon|weapon=level 1 sentry}}
 
| 150 (effectively 450 with the [[Wrangler]] shielding)
 
| 130 [[Metal]]
 
| Semi-Automatic Firing Barrel
 
| '''Damage:'''16 <br> '''Shots per second:''' 4 (8 with [[Wrangler]])<br>'''Average DPS:''' 64 (128 with [[Wrangler]])
 
| 100 rounds
 
|-
 
| height=150 |
 
  
{| class="wikitable grid"
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{{Quotation|'''The Engineer''' on his Mini-Sentry|Ain't that a cute little gun?|sound=Engineer littlesentry02.wav}}
|'''2'''
 
|}
 
[[Image:Lvl2sentry.png|100px]]
 
|{{Icon killicon|weapon=level 2 sentry}}
 
| 180 (effectively 540 with the [[Wrangler]] shielding)
 
| 330 [[Metal]]
 
| Dual Rotational Minigun Barrels
 
| '''Damage:''' 16  <br>'''Shots per second:''' 8 (16 with [[Wrangler]]) <br> '''Average DPS:''' 128 (256 with [[Wrangler]])<br>
 
| 120 rounds
 
|-
 
| height=150 |
 
  
{| class="wikitable grid"
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The '''Combat Mini-Sentry Gun''', also known as '''Mini-Sentry''' or simply '''Mini''', is a more combat-efficient version of the standard Sentry Gun and is a component of the Engineer's [[Gunslinger]] unlock. It is a smaller Level 1 Sentry Gun outfitted with a rotating light that [[Self-illumination|glows]] and is painted with a white checkered paint. Like the Sentry Gun, it can be hauled.
|'''3'''
 
|}
 
[[Image:Lvl3sentry.png|100px]]
 
|{{Icon killicon|weapon=level 3 sentry}}
 
| 216 (effectively 648 with the [[Wrangler]] shielding)
 
| 530 [[Metal]]
 
|
 
Dual Rotational Minigun Barrels <br>
 
  
Target Guided Rocket Launch Support System
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{{Weapon Demonstration|weapon=combat mini-sentry gun|headerlevel=h3}}
|  
 
'''Damage:''' 16  <br>'''Shots per second:''' 8 (16 with [[Wrangler]]) <br> '''Average DPS:''' 128 (256 with [[Wrangler]])<br>
 
*Rockets fire every 3 seconds (slightly faster with the [[Wrangler]]) dealing 102 damage on direct hit
 
|  
 
144 rounds<br>
 
20 rocket salvos
 
  
 +
=== Advantages ===
 +
* Costs only 100 [[Metal]] to place (the normal Sentry costs 130 Metal). This allows an Engineer at a full 200 Metal to build both it and a [[Dispenser]] without needing additional Metal.
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* Constructs much faster than the original Sentry Gun. Hitting the Sentry makes it construct faster and, when deployed after hauling, it is armed in 1.5 seconds.
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* Cheap and disposable means of area denial.
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* Begins construction with 50 health. This makes the Mini-Sentry less vulnerable while under construction when compared to the default Sentry Gun, which begins construction with 1 health.
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* Fires 25% faster than a Level 1 Sentry Gun.
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* Can rotate 35% faster than the default Sentry Gun.
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* 75% the size of a regular Sentry Gun, making it harder to notice and hit.
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* More useful for [[Jumping#Sentry bullet jump|Sentry jumping]], as the firing rate and reduced damage combine to deal more knockback for an equivalent health loss.
  
|}
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=== Disadvantages ===
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* Has only 100 health, compared to a Level 1 Sentry Gun's 150.
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* Cannot be upgraded. The owner and other Engineers can still refill its ammo and health.
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* Deals only 50% the damage per shot of the original Level 1 Sentry Gun. Combined with the 25% faster firing rate, the damage per second is overall 38% lower (~50 DPS compared to the Level 1 Sentry Gun's ~80 DPS).
 +
* Bullets apply significantly less knockback force (800% knockback multiplier compared to a regular Sentry Gun's 1600% multiplier).
 +
* Drops zero Metal when destroyed.
  
'''Combat Mini-Sentry Gun'''[[File:Sentry_Gun_Mini.gif|right|120px]]
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=== Disposable Mini-Sentry ===
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In [[Mann vs. Machine]], the Engineer can buy a Disposable Mini-Sentry that at first glance just looks like a Combat Mini-Sentry Gun; however, there are a few differences:
 +
* Has a slower firing speed than a regular Mini-Sentry.
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* Cannot be repaired or have its ammo refilled.
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* Cannot be destroyed by the Engineer who made it — it can only be destroyed by an enemy [[robot]] or a [[Tank Robot|Tank]] if it's placed on its path.
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** Outside damage sources, the Disposable Mini-Sentry will also be automatically destroyed when a wave is finished or when it runs out of ammo.
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* Cannot be wrangled, but still receives canteen buffs.
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* Has 66% the size of a normal Sentry Gun, compared to the Combat Mini-Sentry Gun's 75% size.
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* Is not affected by the building health upgrade (maximum health cannot go past 100).
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** Is, however, affected by the Sentry Firing Speed upgrade.
  
{| class="wikitable grid"
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== Sentry Gun Levels ==
! class="header" | Level
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{{Sentry Gun level}}
! class="header" | Kill Icon
 
! class="header" | Health
 
! class="header" | Cost
 
! class="header" | Weaponry
 
! class="header" | Damage
 
! class="header" | Ammo
 
|-
 
| height=150 |
 
  
{| class="wikitable grid"
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== Advanced tactics ==
|'''N/A'''
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{{Main|Jumping#Sentry rocket jump}}
|}
 
[[Image:Red Mini Sentry.png|100px]]
 
|{{Icon killicon|weapon=level 1 sentry}}
 
| 100 (effectively 300 with the [[Wrangler]] shielding)
 
| 100 [[Metal]]
 
| Semi-Automatic Firing Barrel
 
| '''Damage:''' 8  <br>'''Shots per second:''' 6 (12 with [[Wrangler]]) <br>'''Average DPS:''' 48 (96 with [[Wrangler]])
 
| 100 rounds
 
|}
 
  
==Related Achievements==
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== Related achievements ==
===General===
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=== {{Achiev type link|general}} ===
{{Show achievement|General|Sentry Gunner|width=50%}}
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{{Achievement table
 +
| 1 = {{Show achievement|General|Sentry Gunner|width=50%}}
 +
}}
  
===Scout===
 
{{Show achievement|Scout|Gun Down|width=50%}}
 
  
===Soldier===
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=== {{Class link|Scout}} ===
 +
{{Achievement table
 +
| 1 = {{Show achievement|Scout|Gun Down|width=50%}}
 +
}}
 +
 
 +
 
 +
=== {{Class link|Soldier}} ===
 
{{Achievement table
 
{{Achievement table
 
| 1 = {{Show achievement|Soldier|Engineer to Eternity}}
 
| 1 = {{Show achievement|Soldier|Engineer to Eternity}}
Line 130: Line 124:
 
}}
 
}}
  
===Demoman===
 
{{Show achievement|Demoman|The Argyle Sap|width=50%}}
 
  
===Engineer===
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=== {{Class link|Demoman}} ===
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{{Achievement table
 +
| 1 = {{Show achievement|Demoman|The Argyle Sap}}
 +
}}
 +
 
 +
 
 +
=== {{Class link|Engineer}} ===
 
{{Achievement table
 
{{Achievement table
| 1 = {{Show achievement|Engineer|Texas Two Step}}
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| 1 = {{Show achievement|Engineer|Best Little Slaughterhouse in Texas}}
 +
      {{Show achievement|Engineer|Breaking Morant}}
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      {{Show achievement|Engineer|Building Block}}
 
       {{Show achievement|Engineer|Deputized}}
 
       {{Show achievement|Engineer|Deputized}}
      {{Show achievement|Engineer|Best Little Slaughterhouse in Texas}}
 
 
       {{Show achievement|Engineer|Doc, Stock and Barrel}}
 
       {{Show achievement|Engineer|Doc, Stock and Barrel}}
      {{Show achievement|Engineer|Pownd on the Range}} 
 
| 2 = {{Show achievement|Engineer|Uncivil Engineer}}
 
 
       {{Show achievement|Engineer|Frontier Justice}}
 
       {{Show achievement|Engineer|Frontier Justice}}
       {{Show achievement|Engineer|If You Build It, They Will Die}}
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       {{Show achievement|Engineer|If You Build It, They Will Die}}
 
       {{Show achievement|Engineer|No Man's Land}}
 
       {{Show achievement|Engineer|No Man's Land}}
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| 2 = {{Show achievement|Engineer|Patent Protection}}
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      {{Show achievement|Engineer|Pownd on the Range}}
 +
      {{Show achievement|Engineer|Revengineering}}
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      {{Show achievement|Engineer|Rio Grind}}
 +
      {{Show achievement|Engineer|Search Engine}}
 +
      {{Show achievement|Engineer|Texas Two Step}}
 +
      {{Show achievement|Engineer|Uncivil Engineer}}
 
}}
 
}}
  
===Medic===
 
{{Show achievement|Medic|Midwife Crisis|width=50%}}
 
  
===Sniper===
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=== {{Class link|Medic}} ===
{{Show achievement|Sniper|De-sentry-lized|width=50%}}
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{{Achievement table
 +
| 1 = {{Show achievement|Medic|Midwife Crisis|width=50%}}
 +
}}
 +
 
  
===Spy===
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=== {{Class link|Sniper}} ===
 +
{{Achievement table
 +
| 1 = {{Show achievement|Sniper|De-sentry-lized|width=50%}}
 +
}}
 +
 
 +
 
 +
=== {{Class link|Spy}} ===
 
{{Achievement table
 
{{Achievement table
 
| 1 = {{Show achievement|Spy|Constructus Interruptus}}
 
| 1 = {{Show achievement|Spy|Constructus Interruptus}}
Line 158: Line 169:
 
}}
 
}}
  
==Bugs==
 
*A bug existed where level 2 and 3 Combat Mini-Sentry Guns could be built by building a normal Level 2 or 3 Sentry Gun, switching to the Gunslinger and hauling and redeploying the existing Sentry Gun. The result of this was a miniature version of the Level 2 and 3 Sentry Guns that gained the properties of the Combat Mini-Sentry, such as the 75% damage and the 4x build speed. These Sentry Guns would always appear to be on the RED team but their characteristic light effect would glow their proper team color. This bug was fixed and subsequently re-added accidentally as of the [[October 8, 2010 Patch]].
 
*The player has the ability to build a Combat Mini-Sentry Gun while having the Wrench or Southern Hospitality equipped, by holding out the blueprints for the sentry with the Gunslinger, and then quickly switching to the Wrench. The player will build a mini-sentry (it will still take away 130 metal). This cannot be done vice versa (AKA Equipping Gunslinger while having normal Sentry blueprints out).
 
*A sapped Mini-sentry will not show an alert on HUD and the Engineer may not say a fitting line.
 
  
==Related Merchandise==
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=== {{Achiev type link|mvm-chievements}} ===
 +
{{Achievement table
 +
| 1 = {{Show achievement|Mann vs. Machievements|Real Steal}}
 +
| 2 = {{Show achievement|Mann vs. Machievements|Undelete}}
 +
}}
 +
 
 +
== Update history ==
 +
{{Update history|
 +
'''{{Patch name|9|20|2007}}'''
 +
* Fixed Sentry muzzleflashes not drawing unless sentry was near the map origin.
 +
 
 +
'''{{Patch name|10|25|2007}}'''
 +
* Engineer buildings now explode when the Engineer dies during [[Sudden Death|sudden death]].
 +
 
 +
'''{{Patch name|11|7|2007}}'''
 +
* Fixed a bug in scoring Engineer building destruction.
 +
 
 +
'''{{Patch name|12|20|2007}}'''
 +
* Sapped buildings now take slightly less damage from the Spy who sapped them.
 +
* {{Undocumented}} Fixed model exploit in stage one allowing Sentry Gun/[[Teleporters|Teleporter]] to be placed behind chain link fence on Dustbowl.
 +
 
 +
'''{{Patch name|2|14|2008}}'''
 +
* Added server log entry for buildings destroyed by their owner.
 +
* Fixed Sentry Gun shadows being clipped.
 +
 
 +
'''{{Patch name|2|28|2008}}'''
 +
* {{Undocumented}} Changed Engineer buildings to detonate when a player disconnects instead of blinking out.
 +
* {{Undocumented}} Fixed Engineer being able to detonate buildings that are being sapped.
 +
 
 +
'''{{Patch name|4|29|2008}}''' ({{update link|Gold Rush Update}})
 +
* Mapmakers can now place Engineer buildings directly into a map, with an option for them to be invulnerable.
 +
 
 +
'''{{Patch name|8|13|2009}}'''
 +
* Fixed Sentry Guns firing at a fully cloaked Spy if they're still the closest target.
 +
 
 +
'''{{Patch name|4|28|2010}}'''
 +
* Killing yourself with your own Sentry Gun no longer increments the Sentry Gun's kill counter.
 +
 
 +
'''{{Patch name|4|30|2010}}'''
 +
* Fixed the Engineer being able to build more than 1 of each type of building.
 +
 
 +
'''{{Patch name|7|8|2010}}''' ({{update link|Engineer Update}})
 +
* Added the ability to haul or move your Sentry Gun, along with having the [[Wrangler]] control the Sentry Gun
 +
* Added a laser light to all sentry models.
 +
* {{Undocumented}} 'Wrenching' a Sentry Gun now upgrades, repairs and restores ammunition all at once per Wrench hit, prioritizing repairs and upgrading if not in possession of enough metal.
 +
 
 +
'''{{Patch name|7|9|2010}}'''
 +
* Fixed an exploit that allowed Engineers to build level 2 or 3 mini Sentry Guns.
 +
 
 +
'''{{Patch name|7|13|2010}}'''
 +
* Fixed an exploit where Engineers could create level 3 mini-Sentry Guns.
 +
 
 +
'''{{Patch name|7|19|2010}}'''
 +
* Fixed an exploit that allowed team kills with Wrangled Sentry Guns.
 +
 
 +
'''{{Patch name|10|18|2010}}'''
 +
* Fixed a Sentry Gun exploit that let Engineers build multiple Sentry Guns.
 +
* (Supposedly) Fixed Engineers being able to build level 3 mini-Sentry Guns using the Wrangler.
 +
 
 +
'''{{Patch name|10|19|2010}}'''
 +
* Fixed another Sentry Gun exploit that let Engineers build multiple Sentry Guns.
 +
* Fixed Engineers being able to build level 3 mini-Sentry Guns using the Wrangler (for real this time).
 +
 
 +
'''{{Patch name|12|17|2010}}''' ({{update link|Australian Christmas}})
 +
* Sentry Guns no longer track Your Eternal Reward Spies after they backstab someone.
 +
 
 +
'''{{Patch name|1|7|2011}}'''
 +
* Updated Sentry kill icons.
 +
 
 +
'''{{Patch name|1|10|2011}}'''
 +
* Combat Mini-Sentry is given a kill icon.
 +
 
 +
'''{{Patch name|1|19|2011}}'''
 +
* Fixed the mini-sentry HUD not playing the alert sound when the sentry is sapped or low on ammo.
 +
 
 +
'''{{Patch name|2|3|2011}}'''
 +
* Engineers who hit teammate's Sentry Guns with their Wrench now get kill assists from that Sentry Gun.
 +
 
 +
'''{{Patch name|3|10|2011}}''' ({{item link|Shogun Pack}})
 +
* Fixed the "Best Little Slaughterhouse in Texas" Engineer achievement not counting Wrangler and Mini-Sentry kills.
 +
 
 +
'''{{Patch name|5|5|2011}}''' ({{update link|Replay Update}})
 +
* {{undocumented}} Sentry Guns now properly target the [[Horseless Headless Horsemann]] as an enemy.
 +
 
 +
'''{{Patch name|4|17|2012}}'''
 +
* Fixed being able to place buildings in nobuild zones.
 +
 
 +
'''{{patch name|6|27|2012}}''' ({{update link|Pyromania Update}})
 +
* Fixed sentry sometimes spawning in shielded mode while the [[Wrangler]] was equipped, but not deployed.
 +
 
 +
'''{{Patch name|8|10|2012}}'''
 +
* Fixed Sentry Gun sometimes placing wrong, being rotated into the ground and pointing upward.
 +
 
 +
'''{{Patch name|3|19|2013}}'''
 +
* Fixed a bug where Sentry Guns would not rotate to face their target under some circumstances.
 +
 
 +
'''{{Patch name|5|13|2013}}'''
 +
* Fixed a bug that allowed level 3 mini-Sentry Guns in [[Mann Vs. Machine]] mode.
 +
 
 +
'''{{Patch name|2|7|2014}}'''
 +
* Fixed the Mini-Sentry range-sphere not accurately displaying the range for the sentry when it is being placed.
 +
* Fixed a [[W:UV mapping|UV]]/skinning problem on the level 1 Sentry Gun.
 +
 
 +
'''{{Patch name|5|15|2014}}'''
 +
* Fixed a bug that would cause the Sentry Gun’s health to look [[Healing#Overheal|overhealed]] when it wasn’t.
 +
 
 +
'''{{Patch name|6|18|2014}}'''
 +
* Sentry bullets are now affected by damage falloff outside of sentry scan range.
 +
* Sentry bullet damage has been changed so it calculates damage based on the Sentry Gun's position, not the Engineer's.
 +
 
 +
'''{{Patch name|9|10|2014}}'''
 +
* Fixed Mini-Sentry collision hull and hitbox being scaled smaller than they should be.
 +
 
 +
'''{{Patch name|1|7|2015}}'''
 +
* Added enemy team {{ent|func_nobuild}} volumes to the capture zone areas in {{code|[[Foundry (Capture the Flag)|ctf_foundry]]}} and {{code|[[Gorge (Capture the Flag)|ctf_gorge]]}} to prevent spawn-camping Sentry Guns.
 +
 
 +
'''{{Patch name|7|23|2015}} #1'''
 +
* Fixed Sentry Guns shooting over the head of Spies using the Box Trot taunt.
 +
 
 +
'''{{Patch name|7|23|2015|no-link=yes}} #2'''
 +
* Fixed Sentry Guns having unlimited ammo.
 +
* Fixed Sentry Gun model being set to level 1 after a [[Sapper]] is removed.
 +
 
 +
'''{{Patch name|12|17|2015}}''' ({{update link|Tough Break Update}})
 +
* After removing a Sapper from a Sentry Gun, there is now a 0.5s delay before the sentry is active again.
 +
* Sentry Guns brought into a respawn room no longer detonate outside of Mann vs. Machine.
 +
 
 +
'''{{Patch name|12|18|2015}}'''
 +
* Fixed a bug with Sentry Guns being disabled for 5 seconds instead of the desired 0.5 seconds after a Sapper is removed.
 +
 
 +
'''{{Patch name|8|29|2016}}'''
 +
* Fixed mini-Sentry Guns not having full health when they are built quickly during the setup time on Mann vs. Machine maps.
 +
 
 +
'''{{Patch name|5|1|2020}}'''
 +
* Fixed an [[Exploits|exploit]] where Sentry Guns could fire through thin walls.
 +
 
 +
'''{{Patch name|7|7|2022}}'''
 +
* Fixed Mini-Sentry Guns not triggering damage alerts in the HUD}}
 +
 
 +
== Bugs ==
 +
* The player has the ability to build the Combat Mini-Sentry Gun, while having any {{botignore|wrench}} equipped, by holding out the blueprints for the Sentry with the Gunslinger and then quickly switching to a {{botignore|wrench}}. The player builds a Mini-Sentry (it still costs 130 Metal). This cannot be done vice versa (equipping the Gunslinger while having normal Sentry blueprints out). If this is done with the [[Jag]] the Sentry gets the construction boost effect.
 +
* Sometimes, when an upgraded Sentry is moved, it fires a bullet between upgrade stages if pointed directly at an enemy or Wrangled.
 +
* Rarely, after removing a [[Sapper]], all of the Sentry Gun's ammunition, including rockets, is completely gone.
 +
* A Wrangled Sentry does not play its rocket-reloading animation.
 +
* Wrangling a Combat Mini-Sentry Gun might result in it remaining in the Wrangled state even when the Wrangler is not the currently active weapon.
 +
** Switching back to the Wrangler corrects the problem.
 +
* After the Mini-Sentry finishes its building animation, it sinks into the ground slightly.
 +
* Occasionally, after being built, a Level 1 Sentry might be frozen in animation and not fire any bullets.
 +
* There still exists a way to get a Leveled Mini-Sentry on some custom maps.
 +
* Sometimes, when a [[Spy]] saps the Sentry Gun during it being constructed, the Engineer cannot destroy the Sapper, making him have to destroy the Sentry Gun, or let the Sapper destroy the Sentry Gun.
 +
* Rarely, when a Sentry Gun has been sapped and the Engineer has changed [[Classes|class]] or left the game, the Sapper appears floating in the air.
 +
* The damage of the Sentry Gun's rockets is calculated based on the distance between the enemy and the Engineer, not the Sentry Gun. Therefore, if the Engineer is closer to the enemy being targeted by the Sentry Gun, it does more damage.
 +
<!-- Please do not add a bug about being able to get stuck inside your Sentry Gun, this is a bug with the Payload Cart and not the Sentry Gun.-->
 +
 
 +
== Unused content ==
 +
* An unused alternate kill icon for the Level 1 Sentry Gun exists in the game files.
 +
 
 +
== Trivia ==
 +
* [[Non-player characters#Radigan Conagher|Radigan Conagher]] created modern Sentry Gun designs by 1890.<ref>[[:File:EngineercomicNT06.jpg|Loose Canon comic]], page 8, Retrieved 2019-03-17</ref> The 1890 and current designs are visually identical.
 +
** Radigan Conagher's notes suggest an earlier steam-powered Sentry Gun design.
 +
* Valve ordered and received a [https://www.teamfortress.com/post.php?id=4773&p=1 full-size motion-tracking model] of a Level 1 Sentry Gun from [[Weta Workshop]].
 +
* Clicking "View the manual" button on the [https://store.steampowered.com/app/440/Team_Fortress_2/ Steam store page of ''Team Fortress 2''] opens an [https://cdn.akamai.steamstatic.com/steam/apps/440/manuals/SentryManual_web.pdf online PDF file] of the [[#Sentry Manual|Sentry Operating Manual]].
 +
** The Sentry Operating Manual uses the [[w:Recycling symbol|recycling symbol]] to tell players they can reuse metal from destroyed equipment. However, that the sign was not created until 1970.
 +
** The cover of the Sentry Operating itself is more like that of the late 1950s to early 1960s, whereas the game itself takes place in July of 1968 (The Calendars). By that point, the font of "Sentry" was outdated and was no longer being used. Industrial (upon which the game is heavily based) used a very basic font even before that.
 +
** The Sentry Operating Manual is in color, which would be wrong for an industrial manual as most are not in color, especially during the 20th century.
 +
* On the back of the Level 3 Sentry Gun's rocket salvo, a tab connects three of the four rockets to the device.
 +
* In ''[[w:Payday 2|Payday 2]]'', on a train robbery mission, the robbers steal a Level 1 Sentry Gun.
 +
 
 +
== Gallery ==
 +
;Sentry Gun levels
 +
<gallery>
 +
File:TF2LVL1SG.png|Level 1 Sentry Gun.
 +
File:TF2LVL2SG.png|Level 2 Sentry Gun.
 +
File:TF2LVL3SG.png|Level 3 Sentry Gun.
 +
File:Sentry Gun Mini.gif|Combat Mini-Sentry Gun.
 +
File:Sentry-to-lvl3.gif|Build to Level 3 animation.
 +
</gallery>
 +
;Development
 +
<gallery>
 +
File:Sentry sketches3.jpg|Sentry Gun concept art.
 +
File:Sentries1.jpg|Sentry Gun concept art.
 +
File:Sentryboom.jpg|Sentry Gun explosion.
 +
File:Sentries3.jpg|Sentry Gun concept art.
 +
File:Sentries2.jpg|Sentry Gun models with ambient occlusion.
 +
</gallery>
 +
;Storyline
 +
The [[Storyline]] was expanded within the [[Engineer Update]]. From ''[[Loose Canon]]'', the ''Sentry Gun Manual'', and the [[:File:Engineer Update Page0.jpg|Engineer Update Page]], it is inferred that Radigan had developed the modern Sentry design before exposure to [[Australium]] and that the Engineer obtained the Sentry plans in the early 1960s from his grandfather's notes.
 +
<gallery>
 +
File:Oldesentry.PNG|Radigan's steam-powered Sentry design.
 +
File:Sentry Gun Loose Canon.png|Radigan's 1890s advanced Sentry design.
 +
</gallery>
 +
;Sentry Gun Operating Manual
 
<gallery>
 
<gallery>
File:Merch Sentry Mousepad.png|[http://store.valvesoftware.com/product.php?i=M0220 Sentry Mousepad]
+
File:Sentry Gun Manual Cover.jpg|Front Cover.
File:Sentry1.jpg|[http://store.valvesoftware.com/product.php?i=P0109 Sentry Poster]
+
File:Sentry Gun Manual Welcome.jpg|Page 2.
 +
File:Sentry Gun Components.jpg|Page 3. Sentry Gun Components.
 +
File:Sentry Gun Manual.jpg|Pages 4-5. Modifying your Sentry.
 +
File:Sentry Gun Manual Promo.jpg|Back Cover.
 +
</gallery>
 +
;Other images
 +
<gallery>
 +
File:Killicon tool chest.png|Icon for a hauled item being destroyed via the Engineer's death.
 +
File:Killicon sentry1 unused.png|Unused Sentry kill icon.
 
</gallery>
 
</gallery>
  
==Trivia==
+
== Merchandise ==
[[File:Sentry Gun Manual.jpg|right|200px|Modifying your Sentry]]
+
{{main|Merchandise}}
*The original Sentry Gun designs were created by [[Non-player characters#Radigan Conagher|Radigan Conagher]] in 1890.<ref>[http://www.teamfortress.com/loosecanon/08.html Team Fortress: Loose Canon (comic)], page 8, retrieved 2010-10-18.</ref>  The original and current designs are visually identical.
+
<gallery>
*The Engineer apparently designed and built the final version of the Sentry Gun under contract from 'TF Industries' in 1965.{{cite}}
+
File:Merch Sentry Mousepad.png|[https://store.valvesoftware.com/product.php?i=M0220 Sentry Mousepad]
*The official game manual for Team Fortress 2 is actually the Sentry Gun Operating Manual.
+
File:Sentry1.png|[https://store.valvesoftware.com/product.php?i=P0109 Sentry Poster]
*A label on the Sentry Gun blueprint reads "Automatic Sentry Gun Apparatus;" however, the Sentry Gun manual refers to it as a "Sentry Gun Mechanical Firing Device".
+
</gallery>
*The Sentry Gun makes a number of beeps every time it reverses its rotation. The number of beeps corresponds to its upgrade level, where a level 3 turret makes three quick beeps. Additionally, the higher the Sentry Gun's level, the louder it is. A level 1 Sentry Gun is slightly harder to hear than a level 3 Sentry Gun; this fact can be used to counter enemy Sentry Guns.
 
*When out of ammunition, a Sentry Gun will continue lock on to enemies and attempt to fire, but will instead make clicking sounds.
 
*Engineers can reach higher standing on a level 1 Sentry Gun than with a Dispenser, making it a better choice on jump and puzzle maps.
 
*An unused alternate kill icon for the level 1 Sentry Gun exists in the game files, seen to the right. It is possible this was a concept icon for kills made with the [[Wrangler]].
 
[[Image:Killicon sentry1 unused.png|framed|right|Unused Wrangler sentry kill icon]]
 
*When the [[Wrangler]] was added in the Engineer Update, all levels of Sentry Gun were given laser sights to accommodate it.
 
*An image appearing on the [[Engineer Update]] page possibly shows very early designs of the modern Sentry Gun.
 
*The flashing light on the Combat Mini-Sentry Gun appears, like the one on the [[Carts|Bomb Cart]], to be attached with duct tape.
 
*Feign deaths produced by the [[Dead Ringer]] will not be added to the Sentry Gun kill/assist counter, but ''will'' contribute to the Best Little Slaughterhouse in Texas achievement.
 
*Mini-Sentry Guns appear to have the exact same stats as the Constructor's Autogun from the fan game [[Gang Garrison 2]] (in terms of health, rate of fire, damage output, inability to upgrade or repair, metal cost, and deployment time). Equipping the Gunslinger also makes the Engineer have "Medic-level" health, just like the Constructor. However this was a coincidence according to Robin Walker. [http://imgur.com/p45uJ.png]
 
*Combat Mini-Sentry Guns share [[gibs]] with standard level 1 Sentry Guns. This means that players will see the light and the checkerboard pattern disappear when a Combat Mini-Sentry Gun is destroyed.
 
*The Combat Mini-Sentry's status in the corner of the HUD will show a upgrade progress bar, despite not being repairable or upgradable.
 
*Valve recently ordered and received a [http://www.teamfortress.com/post.php?id=4773&p=1 full size motion-tracking model] of a level 1 sentry from {{w|Weta Workshop}}.
 
  
 
== References ==
 
== References ==
 +
<references/>
  
<references />
+
== See also ==
 +
* [[Basic Engineer strategy]]
 +
* [[Basic Engineer strategy#Sentry Gun|Sentry Gun placement]]
  
==See also==
+
== External links ==
*[[Engineer strategy]]
+
* [https://cdn.cloudflare.steamstatic.com/steam/apps/440/manuals/SentryManual_web.pdf Sentry Operating Manual]
*[[Engineer strategy#Sentry Placement|Sentry Gun Placement]]
 
  
==External links==
+
{{Engineer Nav}}
*[http://storefront.steampowered.com/Manuals/440/SentryManual_web.pdf Sentry Gun manual]
 
  
{{Engineer Nav}}
 
 
[[Category:Buildings]]
 
[[Category:Buildings]]

Latest revision as of 11:38, 6 December 2024

The Engineer with a Level 3 Sentry

The Sentry Gun (abbreviated to SG), officially known as Sentry Mechanical Firing Device and also known as Sentry or Turret, is a building that can be constructed by the Engineer using the PDA, the Engineer's build tool. The gun itself is a tripodal device constructed of metal, team-colored paint, and a laser sight (when used with the Wrangler).

A level one Sentry Gun is a single-barrel machine gun with an internal magazine. The Sentry has a motion sensor, as stated in Meet the Engineer and the Sentry Manual.

A level two Sentry Gun appears to use an automatic cranking system to rotate the barrel, as indicated by the 2 electric cables visible. It also has 2 Gatling guns and a laser sight is built into the carbine body. Its ammunition is belt-fed.

A level three Sentry Gun is identical to the level two, with the exception of an additional set of rocket silos on the top, which comes out of the back ammunition housing area.

The Sentry Gun functions as an automated turret that fires at the closest enemy within its range and line of sight. Dealing constant as well as consistent damage with noticeable knockback and having an immunity to Critical hits, a Sentry Gun is the cornerstone of a successful defensive setup. On the other hand, they take a while to set up to full potential, and even a fully stocked Sentry Gun can be destroyed with little trouble by a well-executed ÜberCharge or a Spy with his Sapper. Engineers must be on the lookout for such threats to ensure their Sentry Gun's survival. If a Sentry Gun is sapped, it gains a 33% damage resistance against a Spy's weapons.

Functionality

General

The Sentry Gun costs 130 Metal to build, 200 Metal to upgrade to Level 2, and an additional 200 to upgrade to the third and final level totaling to 530 Metal. With each upgrade level, the Sentry Gun becomes more powerful, gaining machine guns, rockets, as well as more health and a minor damage resistance to all Miniguns. The firing range remains constant regardless of level. The Sentry Gun's ammo and health may be replenished with Metal by the Engineer hitting it with his melee weapon. Each bullet reloaded costs 1 Metal and each rocket reloaded costs 2 Metal.

When placing a Sentry Gun, the Engineer can see the limit of its range represented by a team-colored sphere of 1100 Hammer unit radius. A Sentry Gun that is being constructed has health increase gradually until it reaches its maximum health upon completion. While automatically scanning, the Sentry Gun rotates 90 degrees about the direction it is pointing; however, it is capable of detecting and rotating the full 360 degrees to lock on to a target. This takes a brief moment, however, which may allow faster foes to slip past its range. The Sentry Gun can also be manually rotated when placing to face a different direction before building commences. When the blueprint is shown, using the alt-fire button (default key: MOUSE2) rotates the blueprints counterclockwise by 90 degrees.

Properties

As do other Buildings, Sentry Guns emit sound cues to alert players to their presence and status. A scanning Sentry Gun makes a number of beeps every time it reverses its rotation (1, 2 3) — the number of beeps corresponds to its upgrade level, where a Level 3 turret makes three quick beeps. Additionally, this beeping increases somewhat in volume with Level 2 then Level 3 Sentry Gun's level; so, the higher the level, the farther away the Sentry Gun can be heard; this fact can help attentive players find guarded areas. The Sentry Gun's scanning noise sounds slightly different when being fired on by the enemy; slight clicks can be heard along with the regular beeps. The scanning Sentry Gun also makes a distinctive noise when it detects and locks onto an enemy target just before firing — this noise both alerts the enemy of the detection by the Sentry Gun and the team of the presence of an enemy within the range of the Sentry Gun. Enemies detected by a Sentry Gun hear its noise as a slightly different alert noise. All of these scanning noises are silenced when a Sentry Gun is Wrangled.

A Sentry Gun constantly checks if there is an enemy player or building in scanning range with a clear line of sight. If multiple targets meet this criteria, it selects the closest one and switches targets the instant another target is closer, prioritizing players over buildings in its range. Sentry Guns also only attempt to fire once they have lined up with the target, even if firing before then could cause damage to an enemy. Sentry Guns have a maximum rotation and pitching speed when attempting to track a target, which increases with level and is faster than its idle scanning rotation. Sentry Guns still aim and try to fire at enemies even if their ammo reserves are empty.

Sentry Guns cannot see through geometry and Engineer buildings; however, they ignore friendly players.

After running out of valid targets for whatever reason, the Sentry Gun briefly stays pointing in the direction of its last detected target before returning to its scanning sweeps.

Since the Engineer Update, players are able to haul their buildings around. An Engineer carrying his Sentry Gun moves 10% slower and cannot fire or change weapons. A redeployed Sentry Gun retains its previous level and automatically sets up twice as fast. Engineers do not lose any Ammo or Metal by moving Sentry Guns (unless the Sentry Gun was picked up with the Rescue Ranger's alt-fire, which costs 100 metal for moving any building). If the Engineer is killed while hauling his Sentry Gun, it is automatically destroyed along with him and gives a notification in the kill icon area of the screen. Sentry Guns under the effects of a Sapper cannot be picked up.

Like most other weapons, the Sentry Gun's weapons have damage ramp-up and fall-off. Sentry Gun bullet ramp-up and fall-off is calculated based on the distance between the enemy and the Sentry Gun. However, the rockets from a Level 3 Sentry Gun calculate their ramp-up and fall-off based on the distance between the enemy and the Engineer who built the Sentry Gun.

Unlike most other weapons, the Sentry Gun's weapons do not gain Critical hits. It is possible, however, to make the Sentry Gun deal Mini-Crit attacks and damage if its target is coated in Jarate, being Marked For Death, or if the Engineer who built the Sentry Gun is close to a Soldier with an active Buff Banner – boosting the damage of each bullet to 22.

Sentry Guns are controlled by the TF2 server rather than the Engineer's client. That means Sentry Guns behave the same regardless of the connection quality of the Engineer that built them.

Specific properties

Included in the Engineer Update as an unlockable secondary replacement, the Wrangler allows the Engineer to take direct control of his Sentry Gun by "marking" targets manually. Doing so shuts down the Sentry Gun's automated target-lock system but diverts the excess power from the targeting system into speeding up its firing rate, effectively doubling the damage-per-second of the Sentry Gun. The Wrangler also provides the Sentry Gun with a protective shield which absorbs two-thirds of enemy fire while the Wrangler is active. A wrangled Sentry Gun has no maximum range, though its accuracy slightly decreases at longer ranges and its knockback force is halved against targets outside of its normal reach. Once the Engineer switches away from the Wrangler, however, his Sentry Gun is unable to fire for 3 seconds while its auto-lock targeting computer reboots. It is still shielded during this time.

In Mann vs. Machine, Sentry Guns can gain benefits from certain Power Up Canteens. An ÜberCharge Canteen forms a Wrangler-esque shield around the Sentry Gun, reducing incoming damage by 90%. Use of a Kritz Canteen triples the Sentry Gun's firing rate. An Upgrade Buildings Canteen instantly upgrades the Sentry to Level 3 as well as fully repair it, however it does not refill the Sentry Gun's ammo. Sentry Guns can also be upgraded at Upgrade Stations to increase their health and firing rate, and the Engineer can even buy a Disposable Sentry Gun, allowing him to place a second Mini-Sentry that is slightly worse than a Combat Mini-Sentry.

Vulnerabilities

Sentry Guns are damaged by most weapon effects that damage players; however, some effects are modified for Sentry Guns. Also, weapon damage done to a Sentry Gun does not suffer from range falloff, with the exception of any scatter-based weapons or indirect explosions. A destroyed Sentry Gun drops 65 Metal worth of scrap pieces, which can also be picked up by other classes as Ammo.

Sentry Guns do not fire upon enemy Spies that are cloaked. In general, Sentry Guns do not fire upon enemy Spies that are disguised; however, if the Sentry was firing upon the Spy at the time the disguise was activated, it continues to fire upon the Spy until the Spy cloaks, breaks line of sight, or moves out of range. Sentry Guns also do not fire upon enemies in its range if there is a water surface between them or if the enemy is behind cover – this cover includes the Engineer's Dispenser. Sentry Guns are also unable to fire if an enemy Spy attaches a Sapper to it or while they are being upgraded/built. Feign deaths produced by the Dead Ringer are not added to the Sentry Gun kill/assist counter but do contribute to the Best Little Slaughterhouse in Texas achievement.

An Engineer is vulnerable to damage from his own Sentry Gun's bullets. For about the first 300 Hammer units of their flight, Sentry Gun rockets pass through the Sentry Gun's Engineer without detonating as if he were another member of the same team. However, if the rockets do strike another surface within this distance and explode, the Engineer is vulnerable to the resulting splash damage. Beyond this initial distance, the Engineer is fully vulnerable to his own Sentry Gun's rockets (the knockback from Sentry Gun self-damage enables the Engineer to perform bullet and Sentry rocket jumps, especially with the aid of the Wrangler).

Metal spending priority

When an Engineer hits a Sentry Gun with their melee weapon, the metal is spent in a certain order:

  1. Health
  2. Upgrade Progress
  3. Ammo
    1. Bullets
    2. Rockets

However, ammo is usually filled alongside Health and the Sentry Gun's Upgrade Progress. Bullet ammo is refilled first, followed by rocket ammo.[1]

Demonstration

Combat Mini-Sentry Gun

The Combat Mini-Sentries as seen on the Engineer Update page.
Ain't that a cute little gun?
The Engineer on his Mini-Sentry

The Combat Mini-Sentry Gun, also known as Mini-Sentry or simply Mini, is a more combat-efficient version of the standard Sentry Gun and is a component of the Engineer's Gunslinger unlock. It is a smaller Level 1 Sentry Gun outfitted with a rotating light that glows and is painted with a white checkered paint. Like the Sentry Gun, it can be hauled.

Demonstration

Advantages

  • Costs only 100 Metal to place (the normal Sentry costs 130 Metal). This allows an Engineer at a full 200 Metal to build both it and a Dispenser without needing additional Metal.
  • Constructs much faster than the original Sentry Gun. Hitting the Sentry makes it construct faster and, when deployed after hauling, it is armed in 1.5 seconds.
  • Cheap and disposable means of area denial.
  • Begins construction with 50 health. This makes the Mini-Sentry less vulnerable while under construction when compared to the default Sentry Gun, which begins construction with 1 health.
  • Fires 25% faster than a Level 1 Sentry Gun.
  • Can rotate 35% faster than the default Sentry Gun.
  • 75% the size of a regular Sentry Gun, making it harder to notice and hit.
  • More useful for Sentry jumping, as the firing rate and reduced damage combine to deal more knockback for an equivalent health loss.

Disadvantages

  • Has only 100 health, compared to a Level 1 Sentry Gun's 150.
  • Cannot be upgraded. The owner and other Engineers can still refill its ammo and health.
  • Deals only 50% the damage per shot of the original Level 1 Sentry Gun. Combined with the 25% faster firing rate, the damage per second is overall 38% lower (~50 DPS compared to the Level 1 Sentry Gun's ~80 DPS).
  • Bullets apply significantly less knockback force (800% knockback multiplier compared to a regular Sentry Gun's 1600% multiplier).
  • Drops zero Metal when destroyed.

Disposable Mini-Sentry

In Mann vs. Machine, the Engineer can buy a Disposable Mini-Sentry that at first glance just looks like a Combat Mini-Sentry Gun; however, there are a few differences:

  • Has a slower firing speed than a regular Mini-Sentry.
  • Cannot be repaired or have its ammo refilled.
  • Cannot be destroyed by the Engineer who made it — it can only be destroyed by an enemy robot or a Tank if it's placed on its path.
    • Outside damage sources, the Disposable Mini-Sentry will also be automatically destroyed when a wave is finished or when it runs out of ammo.
  • Cannot be wrangled, but still receives canteen buffs.
  • Has 66% the size of a normal Sentry Gun, compared to the Combat Mini-Sentry Gun's 75% size.
  • Is not affected by the building health upgrade (maximum health cannot go past 100).
    • Is, however, affected by the Sentry Firing Speed upgrade.

Sentry Gun Levels

Level Kill icon Health Cost
(Metal)
Weaponry Damage Ammo
1

RED Level 1 Sentry Gun.png

Killicon sentry1.png Without Wrangler shielding: 150

With Wrangler shielding: 450

130 Single barrel machine gun

Damage

  • Maximum ramp-up: 19.49
  • Base damage: 16
  • Maximum fall-off: 8.45

Attack interval

  • Without Wrangler: 0.225 seconds
  • With Wrangler: 0.135 seconds

Average DPS

  • Without Wrangler: 71.11 - 84.44
  • With Wrangler: 118.52 - 140.74
150 rounds
2

RED Level 2 Sentry Gun.png

Killicon sentry2.png Without Wrangler shielding: 180

With Wrangler shielding: 540

330 Twin-mounted Gatling guns

Damage

  • Maximum ramp-up: 19.49
  • Base damage: 16
  • Maximum fall-off: 8.45

Attack interval

  • Without Wrangler: 0.135 seconds
  • With Wrangler: 0.09 seconds

Average DPS

  • Without Wrangler: 118.51 - 140.74
  • With Wrangler: 177.78 - 211.11
200 rounds
3

RED Level 3 Sentry Gun.png

Killicon sentry3.png Without Wrangler shielding: 216

With Wrangler shielding: 648

530 Twin-mounted Gatling guns and rocket salvos Gatling guns

Damage

  • Maximum ramp-up: 19.49
  • Base damage: 16
  • Maximum fall-off: 8.45

Attack interval

  • Without Wrangler: 0.135 seconds
  • With Wrangler: 0.09 seconds

Average DPS

  • Without Wrangler: 118.51 - 140.74
  • With Wrangler: 177.78 - 211.11

Rockets

Damage

  • Maximum ramp-up: 150
  • Base damage: 100
  • Maximum fall-off: 52.81

Falloff is calculated from the distance of the Engineer to the target, not from the Sentry to the target

Attack interval

  • Without Wrangler: 3.06 seconds
  • With Wrangler: 2.25 seconds

Note: Can be reflected with the Pyro's compression blast

200 rounds

20 rocket salvos

Combat Mini-Sentry Gun

Red Mini Sentry.png

Killicon minisentry.png Without Wrangler shielding: 100

With Wrangler shielding: 300

100 Single barrel machine gun

Damage

  • Maximum ramp-up: 9.74
  • Base damage: 8
  • Maximum fall-off: 4.22

Attack interval

  • Without Wrangler: 0.18 seconds
  • With Wrangler: 0.09 seconds

Average DPS

  • Without Wrangler: 44.44 - 55.56
  • With Wrangler: 88.89 - 111.11
150 rounds
Disposable Sentry Gun

Red Mini Sentry.png

Killicon minisentry.png 100 Without Gunslinger: 130

With Gunslinger: 100

Single barrel machine gun

Damage

  • Maximum ramp-up: 9.74
  • Base damage: 8
  • Maximum fall-off: 4.22

Attack interval: 0.225 seconds

Average DPS: 35.56 - 42.22

Note: Only available in Mann vs. Machine as an upgrade and cannot be wrangled, repaired, or have its ammo refilled.

150 rounds

Advanced tactics

Main article: Jumping#Sentry rocket jump

Related achievements

Achieved.png General achievements

Sentry Gunner
Sentry Gunner
Accumulate 10 sentry gun kills with a single sentry.


Leaderboard class scout.png Scout

Gun Down
Gun Down
Destroy an active sentry gun using your pistol.


Leaderboard class soldier.png Soldier

Engineer to Eternity
Engineer to Eternity
Kill an Engineer as he repairs his sentry gun while it's under enemy fire.
Guns of the Navar0wned
Guns of the Navar0wned
Kill 5 Engineer Sentry Guns while you are standing outside of their range.


Leaderboard class demoman.png Demoman

The Argyle Sap
The Argyle Sap
Blow up an Engineer, his sentry gun, and his dispenser with a single stickybomb detonation.


Leaderboard class engineer.png Engineer

Best Little Slaughterhouse in Texas
Best Little Slaughterhouse in Texas
Rack up 5000 kills with your sentry guns.


Breaking Morant
Breaking Morant
Kill 10 Snipers with a sentry gun under the control of your Wrangler.


Building Block
Building Block
Have a sentry shielded by the Wrangler absorb 500 damage without being destroyed.


Deputized
Deputized
Get 10 assists with another Engineer where a sentry gun was involved in the kill.


Doc, Stock, and Barrel
Doc, Stock, and Barrel
Repair a sentry gun under fire while being healed by a Medic.


Frontier Justice
Frontier Justice
Have your sentry kill the enemy that just killed you within 10 seconds.


If You Build It, They Will Die
If You Build It, They Will Die
Haul a level 3 sentry gun into a position that achieves a kill shortly after being redeployed.


No Man's Land
No Man's Land
Use a sentry gun to kill 25 enemy players that are capturing a point.
Patent Protection
Patent Protection
Destroy an enemy Engineer's sentry gun with a sentry under control of your Wrangler.


Pownd on the Range
Pownd on the Range
Kill 10 enemies outside the normal sentry gun range using the Wrangler.


Revengineering
Revengineering
Use a revenge crit to kill the enemy player that destroyed your sentry gun.


Rio Grind
Rio Grind
Perform 50 repairs and/or reloads on a Sentry gun being Wrangled by another Engineer.


Search Engine
Search Engine
Kill 3 cloaked Spies with a sentry gun under control of your Wrangler.


Texas Two-Step
Texas Two-Step
Use your shotgun to finish off an enemy recently damaged by your sentry gun.


Uncivil Engineer
Uncivil Engineer
Provide an enemy player with a freeze cam of you and the sentry that just killed them.


Leaderboard class medic.png Medic

Midwife Crisis
Midwife Crisis
Heal an Engineer as he repairs his sentry gun while it's under enemy fire.


Leaderboard class sniper.png Sniper

De-sentry-lized
De-sentry-lized
Destroy 3 Engineer sentry guns.


Leaderboard class spy.png Spy

Constructus Interruptus
Constructus Interruptus
Kill an Engineer who is working on a sentry gun.
Joint Operation
Joint Operation
Sap an enemy sentry gun within 3 seconds of a teammate sapping another.


Mvm navicon.png Mann vs. Machievements

Real Steal
Real Steal
As an Engineer, escape with your sentry as a sentry buster is about to detonate.
Undelete
Undelete
During a wave, use a canteen charged with 'Instant Building Upgrade' to build a new sentry gun within 3 seconds of your previous sentry gun's destruction.

Update history

September 20, 2007 Patch
  • Fixed Sentry muzzleflashes not drawing unless sentry was near the map origin.

October 25, 2007 Patch

  • Engineer buildings now explode when the Engineer dies during sudden death.

November 7, 2007 Patch

  • Fixed a bug in scoring Engineer building destruction.

December 20, 2007 Patch

  • Sapped buildings now take slightly less damage from the Spy who sapped them.
  • [Undocumented] Fixed model exploit in stage one allowing Sentry Gun/Teleporter to be placed behind chain link fence on Dustbowl.

February 14, 2008 Patch

  • Added server log entry for buildings destroyed by their owner.
  • Fixed Sentry Gun shadows being clipped.

February 28, 2008 Patch

  • [Undocumented] Changed Engineer buildings to detonate when a player disconnects instead of blinking out.
  • [Undocumented] Fixed Engineer being able to detonate buildings that are being sapped.

April 29, 2008 Patch (Gold Rush Update)

  • Mapmakers can now place Engineer buildings directly into a map, with an option for them to be invulnerable.

August 13, 2009 Patch

  • Fixed Sentry Guns firing at a fully cloaked Spy if they're still the closest target.

April 28, 2010 Patch

  • Killing yourself with your own Sentry Gun no longer increments the Sentry Gun's kill counter.

April 30, 2010 Patch

  • Fixed the Engineer being able to build more than 1 of each type of building.

July 8, 2010 Patch (Engineer Update)

  • Added the ability to haul or move your Sentry Gun, along with having the Wrangler control the Sentry Gun
  • Added a laser light to all sentry models.
  • [Undocumented] 'Wrenching' a Sentry Gun now upgrades, repairs and restores ammunition all at once per Wrench hit, prioritizing repairs and upgrading if not in possession of enough metal.

July 9, 2010 Patch

  • Fixed an exploit that allowed Engineers to build level 2 or 3 mini Sentry Guns.

July 13, 2010 Patch

  • Fixed an exploit where Engineers could create level 3 mini-Sentry Guns.

July 19, 2010 Patch

  • Fixed an exploit that allowed team kills with Wrangled Sentry Guns.

October 18, 2010 Patch

  • Fixed a Sentry Gun exploit that let Engineers build multiple Sentry Guns.
  • (Supposedly) Fixed Engineers being able to build level 3 mini-Sentry Guns using the Wrangler.

October 19, 2010 Patch

  • Fixed another Sentry Gun exploit that let Engineers build multiple Sentry Guns.
  • Fixed Engineers being able to build level 3 mini-Sentry Guns using the Wrangler (for real this time).

December 17, 2010 Patch (Australian Christmas)

  • Sentry Guns no longer track Your Eternal Reward Spies after they backstab someone.

January 7, 2011 Patch

  • Updated Sentry kill icons.

January 10, 2011 Patch

  • Combat Mini-Sentry is given a kill icon.

January 19, 2011 Patch

  • Fixed the mini-sentry HUD not playing the alert sound when the sentry is sapped or low on ammo.

February 3, 2011 Patch

  • Engineers who hit teammate's Sentry Guns with their Wrench now get kill assists from that Sentry Gun.

March 10, 2011 Patch (Shogun Pack)

  • Fixed the "Best Little Slaughterhouse in Texas" Engineer achievement not counting Wrangler and Mini-Sentry kills.

May 5, 2011 Patch (Replay Update)

April 17, 2012 Patch

  • Fixed being able to place buildings in nobuild zones.

June 27, 2012 Patch (Pyromania Update)

  • Fixed sentry sometimes spawning in shielded mode while the Wrangler was equipped, but not deployed.

August 10, 2012 Patch

  • Fixed Sentry Gun sometimes placing wrong, being rotated into the ground and pointing upward.

March 19, 2013 Patch

  • Fixed a bug where Sentry Guns would not rotate to face their target under some circumstances.

May 13, 2013 Patch

February 7, 2014 Patch

  • Fixed the Mini-Sentry range-sphere not accurately displaying the range for the sentry when it is being placed.
  • Fixed a UV/skinning problem on the level 1 Sentry Gun.

May 15, 2014 Patch

  • Fixed a bug that would cause the Sentry Gun’s health to look overhealed when it wasn’t.

June 18, 2014 Patch

  • Sentry bullets are now affected by damage falloff outside of sentry scan range.
  • Sentry bullet damage has been changed so it calculates damage based on the Sentry Gun's position, not the Engineer's.

September 10, 2014 Patch

  • Fixed Mini-Sentry collision hull and hitbox being scaled smaller than they should be.

January 7, 2015 Patch

July 23, 2015 Patch #1

  • Fixed Sentry Guns shooting over the head of Spies using the Box Trot taunt.

July 23, 2015 Patch #2

  • Fixed Sentry Guns having unlimited ammo.
  • Fixed Sentry Gun model being set to level 1 after a Sapper is removed.

December 17, 2015 Patch (Tough Break Update)

  • After removing a Sapper from a Sentry Gun, there is now a 0.5s delay before the sentry is active again.
  • Sentry Guns brought into a respawn room no longer detonate outside of Mann vs. Machine.

December 18, 2015 Patch

  • Fixed a bug with Sentry Guns being disabled for 5 seconds instead of the desired 0.5 seconds after a Sapper is removed.

August 29, 2016 Patch

  • Fixed mini-Sentry Guns not having full health when they are built quickly during the setup time on Mann vs. Machine maps.

May 1, 2020 Patch

  • Fixed an exploit where Sentry Guns could fire through thin walls.

July 7, 2022 Patch

  • Fixed Mini-Sentry Guns not triggering damage alerts in the HUD

Bugs

  • The player has the ability to build the Combat Mini-Sentry Gun, while having any wrench equipped, by holding out the blueprints for the Sentry with the Gunslinger and then quickly switching to a wrench. The player builds a Mini-Sentry (it still costs 130 Metal). This cannot be done vice versa (equipping the Gunslinger while having normal Sentry blueprints out). If this is done with the Jag the Sentry gets the construction boost effect.
  • Sometimes, when an upgraded Sentry is moved, it fires a bullet between upgrade stages if pointed directly at an enemy or Wrangled.
  • Rarely, after removing a Sapper, all of the Sentry Gun's ammunition, including rockets, is completely gone.
  • A Wrangled Sentry does not play its rocket-reloading animation.
  • Wrangling a Combat Mini-Sentry Gun might result in it remaining in the Wrangled state even when the Wrangler is not the currently active weapon.
    • Switching back to the Wrangler corrects the problem.
  • After the Mini-Sentry finishes its building animation, it sinks into the ground slightly.
  • Occasionally, after being built, a Level 1 Sentry might be frozen in animation and not fire any bullets.
  • There still exists a way to get a Leveled Mini-Sentry on some custom maps.
  • Sometimes, when a Spy saps the Sentry Gun during it being constructed, the Engineer cannot destroy the Sapper, making him have to destroy the Sentry Gun, or let the Sapper destroy the Sentry Gun.
  • Rarely, when a Sentry Gun has been sapped and the Engineer has changed class or left the game, the Sapper appears floating in the air.
  • The damage of the Sentry Gun's rockets is calculated based on the distance between the enemy and the Engineer, not the Sentry Gun. Therefore, if the Engineer is closer to the enemy being targeted by the Sentry Gun, it does more damage.

Unused content

  • An unused alternate kill icon for the Level 1 Sentry Gun exists in the game files.

Trivia

  • Radigan Conagher created modern Sentry Gun designs by 1890.[2] The 1890 and current designs are visually identical.
    • Radigan Conagher's notes suggest an earlier steam-powered Sentry Gun design.
  • Valve ordered and received a full-size motion-tracking model of a Level 1 Sentry Gun from Weta Workshop.
  • Clicking "View the manual" button on the Steam store page of Team Fortress 2 opens an online PDF file of the Sentry Operating Manual.
    • The Sentry Operating Manual uses the recycling symbol to tell players they can reuse metal from destroyed equipment. However, that the sign was not created until 1970.
    • The cover of the Sentry Operating itself is more like that of the late 1950s to early 1960s, whereas the game itself takes place in July of 1968 (The Calendars). By that point, the font of "Sentry" was outdated and was no longer being used. Industrial (upon which the game is heavily based) used a very basic font even before that.
    • The Sentry Operating Manual is in color, which would be wrong for an industrial manual as most are not in color, especially during the 20th century.
  • On the back of the Level 3 Sentry Gun's rocket salvo, a tab connects three of the four rockets to the device.
  • In Payday 2, on a train robbery mission, the robbers steal a Level 1 Sentry Gun.

Gallery

Sentry Gun levels
Development
Storyline

The Storyline was expanded within the Engineer Update. From Loose Canon, the Sentry Gun Manual, and the Engineer Update Page, it is inferred that Radigan had developed the modern Sentry design before exposure to Australium and that the Engineer obtained the Sentry plans in the early 1960s from his grandfather's notes.

Sentry Gun Operating Manual
Other images

Merchandise

Main article: Merchandise

References

  1. Uncle Dane - Engineer Rules
  2. Loose Canon comic, page 8, Retrieved 2019-03-17

See also

External links