Prima Games eGuides Fallout 4 eGuide

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Fallout 4 eGuide DATA The Institute Quests

Mass Fusion

1. Speak with Allie Filmore

2A. Relay to Mass Fusion

2B. Inform the Brotherhood

3. Locate the Beryllium Agitator

4. Retrieve the Executive Keycard

5. Proceed to the reactor level

6. (Optional) Restore power to the elevator

7. Retrieve the Beryllium Agitator

8. Unlock the reactor

9. Take the Beryllium Agitator

10. Eliminate reactor level security

11. Exit Mass Fusion

12. (Optional) Assist Institute forces in the lobby

13. Speak with Allie Filmore

Locations to Explore
  • Mass Fusion

Testing Your Loyalties

After speaking to the scientist Allie Filmore, you agree to help her find something called a “Beryllium Agitator” from the ruins of Mass Fusion. Decide whether she’ll accompany you or not; then you must make a potentially epoch-defining decision. You can:

  • Relay to Mass Fusion and continue your loyalty to the Institute. This quest continues (below), several Brotherhood of Steel quests fail, and Brotherhood of Steel Quest: Brotherhood of Steel Shutdown begins.
  • Leave the Institute, visit the Brotherhood of Steel, and inform them, switching your loyalties to them. The Brotherhood of Steel Quest: Spoils of War begins.

Mass Confusion

You relay to the Mass Fusion skyscraper roof, in the Financial District of Boston. After neutralizing all threats, descend one floor to the executive suites, and locate the balcony desk before the room with the Executive Research Lab Terminal. Gather the following from the desk:

Mass Fusion Executive Lab Password

Mass Fusion Executive ID

Now you can access the Executive Research Lab Terminal (Advanced) with a password. Read the personal intramails; the item you seek is in the facility’s basement. And you’re on the roof.

At the elevator, swipe the Mass Fusion Executive ID through the card reader. Ride the elevator all the way down, taking pot shots at enemy forces along the way. When the coast is clear, you can:

(Optional) Locate the circuit breaker in the chamber to the north and above your current position. Flip the breaker to power the elevator. Then return, swipe the ID card, and ride the elevator down to the lobby, maximizing enemy casualties as you go.

Locate the room to the north of your current position. Locate the Mass Fusion Labs Key on the desk. Use it to open the door to the adjacent chamber with the hole in the floor. Drop down, and continue a manual descent through the floors to the lobby, removing any potential enemy threats along the way.

Mass Fusion Labs Key

Expect more enemy resistance in the lobby. Search for the service elevator, swiping your ID card to access it.

Beryllium Agitation

After stepping into the decontamination area (press that button!), move into the reactor chamber. Press the interlock release and activate the agitator receptacle. Grab what you came here for.

Beryllium Agitator

The facility’s robotic defenses are automatically activated. Reach the outer reactor room and engage a Sentry Bot and Protectron. After using your ID card to open the main door, bring your defenses to bear on an Assaultron. Then ascend the stairs to nullify another Protectron without being scorched by a laser turret.

Exit to the lobby. If you have the ammunition and abilities, help Institute forces rid the lobby of threats. Then rendezvous with Allie Filmore back inside the Institute.