Sentry Bot (Fallout 3)

The Sentry Bot (military serial numbers SB-XXXX) is a military robot model made before the Great War. A different Sentry Bot model was used in military bases in California, while this one has been seen mainly in the Capital Wasteland. They have two arms that end with deadly weapons (a Minigun or Gatling Laser and a Missile Launcher), and three legs that end with wheels.

Sentry Bots are extremely heavily armored and take significant amounts of small arms or energy weapons fire, or even multiple missile shots, to destroy. They have excellent resistance against both conventional projectiles and energy weapons, and can soak many more rounds than even a Deathclaw. They also do not seem to take additional damage from headshots (in fact, your weapons seem to do better damage aimed at their torso rather than aimed at their head).

Sentry Bots are the highest level robot NPCs in Fallout 3, and are much more powerful opponents than Protectrons, Robobrains, and Mr. Gutsys.

Appearances
This sentry bot model appears only in Fallout 3. A similar robot appears in Fallout 2 also armed with minigun and missiles, however with different design.

Tactics

 * One quick way to get past these metal hulks is to throw a pulse grenade at them which temporarily disables the robot (though sometimes it seems to make the robot go faster). With this window of opportunity, unload on the robot without fear of reprisal.
 * Cripple its missile launcher arm then fire from a distance.
 * Cripple the minigun arm and attack up close.
 * Shooting them in either arm seems to do more damage than anywhere else.
 * When facing a solitary Sentry Bot, the combination of its slow movement and charge up time of its gatling lasers/minigun makes it possible for you to circle strafe around it without it being able to fire any shots at you.
 * Sentry Bots have high resistance against fire based weapon such as Flamer. However, Shishkebab surprisingly deals incredible damage to Sentry Bots. But if you have your flamer pointed at the center or the head, excluding the VATS it will do more damage, if you have the Burnmaster, it will be more effective
 * Due to their innate ability to ignore enemy DR, Deathclaw Gauntlets are also an ideal weapon, and can destroy a Sentry Bot with just a few strikes.
 * Provided you can close distance, the best tactic is to use the Shishkebab or Deathclaw Gauntlet and strafe around it in a circle. Change directions from clockwise to counterclockwise to confuse it even more, and it will never fire a single shot.
 * When facing a Sentry Bot with conventional weaponry only, keep in mind that its weapons are mounted relatively low on its chassis and far from its center. This can allow you to make attacks on the Sentry´s body from above or from behind cover while blocking the Sentry´s line of fire.
 * Due to its slow movement speed, if you can get behind it you can melee it to your hearts content.