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Proper Vault-Tec ID not present! Engaging target!

The Masterbrain is a unique robobrain that controls all the other security robots in the Vault-Tec headquarters in the year 2277. It roams the Vault-Tec administration level but is most likely found near a turret control terminal slightly left of the level's center.


The Masterbrain was manufactured for the Vault-Tec Corporation to act as a kill-switch for all other robotic security measures within the headquarters and still remains active 200 years after the Great War. The Masterbrain is identified by the large Vault-Tec logo on its chassis.

Interactions with the player character

Interactions overview

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This character has no special interactions.

Effects of player's actions

If it is defeated and the Lone Wanderer interacts with it, it will say "You have accessed the Masterbrain's internal mechanism. If you destroy its uplink, it will cause all the automated security units in Vault-Tec to shut down." If they choose to do so, this will disable all other robots in the Vault-Tec headquarters building, with the exception of the automated turrets.

Other interactions

The player character can shut down Masterbrain using three terminals scattered throughout the building. It is also possible to disable it using the Robotics Expert perk.



  • Masterbrain is the only known robobrain without a visible brain. The brain may have been visible before the glass was covered with dirt.
  • Masterbrain's paint scheme is unique, and none of the other robobrains in the Capital Wasteland have it.

Notable quotes


The Masterbrain appears only in Fallout 3.