Fallout: Brotherhood of Steel/Walkthrough

Chapter One
Brotherhood members have gone missing in Carbon, and the chosen Initiate is tasked with searching for the paladins, starting with the nearby town. The Initiate is welcomed by a prostitute, Ruby. Armed thugs loiter in town and harass Armpit, a bartender. Armpit is grateful the Initiate saves him, and steers the Initiate in the direction of the shifty mayor of this lawless town, Richard.

The mayor might be due some choice words from the electorate for the state of his town; one, in particular, will give the Initiate a discount as a reward for telling off the mayor. Even this outburst won't make the mayor reveal the location of the missing paladins. He insists the Initiate clear out an infestation of radscorpions in the nearby warehouse. The Initiate can collect the scorpion tails and whatever contents of the warehouse that aren't nailed down, which Armpit is interested in buying. When all the giant, radioactive, and the more common mutated scorpions are all rendered lifeless, the Initiate returns to the mayor. The mayor reveals the missing paladins headed off in the direction of a massive crater outside of town.

Following the trail to the bottom, the Initiate finds that the mayor was threatened by the raiders who seek revenge for the ones killed in the bar; lure the Initiate on the outskirts so they can be killed, or have Carbon be burned to the ground. The mayor then turns homicidal as well, mentioning that he is not normally a violent man, but the thought of killing the Initiate seems enjoyable. Mayor Richard has more explosives on him than anyone really ought to be able to carry, and is determined to unload as much of it as possible in the Initiate's vicinity. Despite this, the end result is the mayor's demise. The Initiate returns to the town.

The raiders have given up loitering in favor of looting. Their leader, Jane, shows her sadistic side by ordering her men to burn Armpit to death. Many of the citizens of the town have fled; one who couldn't make it to their refuge in the recently cleared warehouse requests the Initiate's aid in saving them. But first, there are a total of 37 citizens scattered throughout the town areas. The bandits inside, and their leader, are doing what they do best; getting in the way. The Initiate finds ways to make them less obstructive.

Inside a mill, the Initiate finds Jane. She reveals that she helped the Brotherhood of Steel when she met with a group of paladins who wanted information on super mutant activity in the area. She directed them to a mutant army that was located at the nearby ghoul city of Los. She then reveals that the paladins not only knew about her activities in Carbon but they also offered her protection. She is then killed by the Initiate in combat, and they head to the city of Los.

Chapter Two
In Los, the Initiate looks for mutants. The search leads to the Church of the Lost, a cult based inside the city. A Brotherhood paladin, Rhombus, asks the Initiate to kill the cult leader, Blake. Blake and the Initiate fight, and after recovering a key from the dead cult leader, the Initiate escorts Rhombus to a truck where he had hidden the key.

When they try to recover the key, it will be guarded by kamikaze ghouls. The Initiate, warned of the danger, kills all the kamikaze ghouls in the area. Rhombus, seriously wounded, gives the Initiate the key card and entrusts the task of stopping the super mutants. The Initiate asks the Los ghouls for information and one of them speaks of a warehouse and a Secret Vault to be found not far from the current location. The Initiate finds the warehouse and goes inside.

After fighting in the warehouse, the Initiate manages to revive an old generator and takes an elevator that overlooks the entrance to the Secret Vault. Here, two super mutants activate turrets, which the Initiate must destroy. After all that, the Initiate uses the key card to open the door of the armored shelter and enter.

Chapter Three
During a battle with Attis, the mutant general, the Initiate is knocked unconscious and left for dead, with their left arm cut off. Mary, a young woman who has lived her life in the vault, finds the Initiate and guides them to safety. The Initiate receives a new arm thanks to the generosity and technology of the scientists. The Initiate meets Patty, a security officer of the vault. Patty explains how they are trapped in the vault, ever since their own security officer, Blake, was involved in a local civil war between the guards and the scientists, after Blake convinced the guards the scientists' research was evil due their methods. As a result of an explosion, the guards returned to the surface, transforming into the ghouls of Los, while the scientists became trapped in the vault. The Initiate reveals to Patty how super mutants are targeting their vault. Seeking a way to escape before the mutants arrive, Patty asks the Initiate to help disable the ventilation systems so an auxiliary shaft will open.

The super mutants begin infiltrating the vault and begin slaughtering its inhabitants. The Initiate finds Attis who reveals the mutants want to control the vault because it focused on curing sterility due to mutation. Attis seeks to allow him and his super mutants to reproduce with each other so their species can thrive. However, when Attis tries the chemical compound, he claims it does not work, although he begins mutating to become more powerful, and is excited he can follow in his Master's footsteps.

The Initiate defeats a mutated Attis, whose remains scatter and grow around the vault, infesting the substructure with polyp-like growths. While escaping, the Initiate discovers Patty who has been consumed by a blob which is eating her. Patty mentions she stayed behind in an attempt to eliminate all research so the super mutants could not recreate FEV or use it for their agenda. She asks the Initiate to head to the decontamination center to gain access to a computer terminal that can start the decontamination of the vault; in this case, a large explosion which will eradicate the vault. Patty then asks the Initiate for a mercy killing. The Initiate then runs to amonorail car, narrowly escaping the now self-destructing vault. During the explosion, Cyrus, Nadia and Cain are seen watching Los from the city's outskirts.