Sentry Gun

“

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 Engineer

”

The Sentry Gun (sometimes known as a "Turret", "Sentry" 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 (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.

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 salvo costs 2 metal.

When placing a Sentry Gun, the limit of its range is represented by a 3D sphere of your team color. A Sentry that is being constructed will have its health increase gradually until it reaches its maximum health upon completion. The Sentry 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 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 clockwise by 90 degrees.

Sentry Guns will not fire upon enemy Spies that are cloaked or disguised. 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.

Unlike most other weapons, the Sentry Gun's weapons do not get affected with damage falloff from range nor can it gain criticals. It is possible however, to make the Sentry Gun deal Mini crit attacks and damage if its target is coated in Jarate or if the Engineer who built the sentry is close to a Soldier with an active Buff Banner, boosting the damage of each bullet to 22.

Since the Engineer Update, players are able to pick up and move their sentries around. The Sentry retains its level after being transported in the Toolbox.

Also included in the Engineer Update is an unlockable Pistol replacement, The Wrangler, which allows the Engineer to take direct control of his Sentry Gun by 'marking' targets manually. Doing so shuts down the Sentry's automated target-lock system, but diverts the excess power from the targeting system into speeding its firing rate, effectively doubling the damage-per-second of the Sentry. 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 shuts off and pockets the Wrangler, however, his Sentry Gun is left defenseless for 3 seconds while its auto-lock targeting computer reboots.

Sentry Gun Levels

Level	Kill Icon	Health	Cost	Weaponry	Damage	Ammo
1		150 (effectively 450 with the Wrangler shielding)	130 Metal	Semi-Automatic Firing Barrel	14-18 damage 4 (8 with Wrangler) shots per second 64 (128 with Wrangler) average DPS	100 bullets
2		180 (effectively 540 with the Wrangler shielding)	330 Metal	Dual Rotational Minigun Barrels	14-18 damage 8 (16 with Wrangler) shots per second 128 (256 with Wrangler) average DPS	120 bullets
3		216 (effectively 648 with the Wrangler shielding)	530 Metal	Dual Rotational Minigun Barrels Target Guided Rocket Launch Support System	14-18 damage (bullets), 8 (16 shots with Wrangler) shots per second for 128 (256 with Wrangler) average DPS Rockets fire every 3 seconds (slightly faster with the Wrangler) dealing 100 damage on direct hit	144 Bullets 20 rocket salvos
N/A		100 (effectively 300 with the Wrangler shielding)	100 Metal	Semi-Automatic Firing Barrel	7-9 damage 6 (12 with Wrangler)shots per second 48 (96 with Wrangler)average DPS	100 bullets

Combat Mini-Sentry Gun

A RED Mini-Sentry Gun

“

Sometimes, you just need a little less gun. Click to listen — The Engineer

”

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, and is deployed at full health. 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 75% the damage of the original Level 1 Sentry Gun.

Trivia

Modifying your Sentry

• The original Sentry Gun designs were created by Radigan Conagher in 1890 [1]. The original and current designs are visually identical.
• The Engineer apparently designed and built the final version of the Sentry Gun under contract from 'TF Industries' in 1965.
• The official game manual for Team Fortress 2 is actually the Sentry Gun Operating Manual.
• Engineers can receive a "Sentry Gunner" achievement for racking up 10 kills with a single Sentry Gun; the Engineer can die, as long as the Sentry Gun does not.
• A label on the Sentry Gun blueprint reads "Automatic Sentry Aparatus;" however, the Sentry Gun manual refers to it as a "Sentry Mechanical Firing Device".
• Like all Buildings, Sentry Guns can be built underwater.
• Sentry Guns cannot fire through a Dispenser built by an Engineer of the same team.
• 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's level, the louder it is. A level 1 sentry is slightly harder to hear than a level 3 Sentry; 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.
• Due to a bug, the rockets from a Sentry Gun may sometimes damage teammates if the Sentry Gun is destroyed as the rockets are in-flight.
• An unused alternate kill icon for the level 1 Sentry Gun exists in the game files, seen to the right. This was most likely for the Wrangler, as it uses a laser sight mechanic similar to the mentioned kill icon.

Unused level 1 sentry kill icon

• When the Wrangler was added in the Engineer Update, all levels of Sentry Gun were given laser sights to accommodate it.
• A bug existed where level 2 and 3 Combat Mini-Sentries could be built by building a normal Level 2 or 3 Sentry, switching to the Gunslinger and hauling and redeploying the existing Sentry. The result of this was a miniature version of the Level 2 and 3 Sentries that gained the properties of the Combat Mini-Sentry, such as the 75% damage and the 4x build speed. These Sentries would always appear to be on the RED team but their characteristic light effect would glow their proper team color. This bug has not been fully fixed and is still able to be exploited.

External links

• Sentry Gun manual