Even if you havenвЂ™t fired a single shot before this point, the Sentry Bot will be defeated, just make sure you create distance between yourself and the hulking robot. You should be able to destroy them during a single round of V.A.T.S. The fusion cores on the Sentry BotвЂ™s back are pretty weak. Use this opportunity to dash to a place where you can see the now exposed fusion cores on its upper back. Instead, wait for this phase to end, and then it will stop and cool off for a very short period of time. Do not engage when it is like this, it will literally just mow you down. That is, unless you wait for a specific attack.ДЄs you fight the Sentry bot, it will go through a phase where it glows and lets off a lot of steam, pretty much going berserk for about 20 seconds or so. Sentry bots have the same health as a Deathclaw, but unlike a Deathclaw they have no weak points and take no extra damage from head shots. Sentry Bots can take a large amount of damage from Small Guns and Energy Weapons. They are the strongest robots found within the Capital Wasteland. This robot can sense when there is a threat behind it and will instantly turn. Sentry Bots were a military robot that was commissioned before the Great War.

A Sentry BotвЂ™s weak spot is right on its back, but youвЂ™ll need to wait before you can take a stab at it. They have really tough armor, and can turn on a dime. They are all black and armed with a mini-gun, a charging ability, smoke, and just all around meanness. These are those huge robots with four legs that end in wheels. They are a nightmare when in a room with lots of cover, but are downright impossible to face out in the open. Be thankful that these guys are pretty rare.

Fallout 3 sentry bot