Shadow of Steel

Shadow of Steel is a Brotherhood of Steel main quest in Fallout 4.

Detailed walkthrough
After observing a huge Brotherhood of Steel airship pass overhead, the Sole Survivor's Pip-Boy radio receives a transmission. Listen to it for further instructions before heading to the Cambridge Police Station and following Paladin Danse to the roof.

After a short Vertibird flight to the Brotherhood of Steel's flagship, the Prydwen, disembark onto the flight deck and meet Lancer Captain Kells.

One is ordered to attend an address being given by Elder Maxson. Speak to Maxson afterwards. Regardless of the earlier rank in the Brotherhood, Maxson now bestows the title of knight on the Sole Survivor and a new suit of power armor, which can be found in Bay 3 of the main deck.

Nick Valentine dialogue

 * When speaking to Paladin Danse at the beginning of the quest
 * Diplomacy : "It sure as hell ain't gonna be taken as a gesture of good faith from the other forces in the Commonwealth."
 * Provoking War : "No one brings that much firepower without plans to use it." [Valentine liked that.]
 * Who is Maxson? : Valentine will call Maxson a lunatic.
 * Quick War : Valentine will ask "Yeah, for who?" [Valentine disliked that.]

Hancock dialogue

 * Diplomacy : "Ain't no one in the Commonwealth wondering about your intentions now."
 * Provoking War : "Folks don't usually appreciate having a floating fortress blocking their view."
 * Quick War : "Sure know how to make an entrance, I'll give you that."

Piper dialogue

 * Diplomacy : Piper will exclaim "What have you done?"
 * Provoking War : "You're right. There's no way this doesn't lead to more death." [Piper liked that.]
 * Who is Maxson? : "He's a dangerous man, that's what he is."
 * Quick War : "You two can't be that naive. That thing, it's just gonna escalate everything. You can't honestly believe it will stem the bloodshed?" [Piper disliked that.]

Bugs

 * If you did not complete Call to Arms before the Prydwen appears after Reunions, this will trigger a glitch where Brotherhood Vertibird patrol teams will not spawn correctly.
 * If an NPC clips through Paladin Danse while you are reporting to him, the dialogue options may disappear and cannot be pulled back up. When you try to talk to him again, he will only say "I'll be in the mess hall if you need me. Good luck with Maxson," making the quest impossible to complete, and will leave you unable to talk to most of the other Brotherhood of Steel members. Dismissing any companions before talking to Danse may fix the issue.
 * If you do not leave via the elevator, the Shadow of Steel quest won't trigger. You need to exit through the elevator door.
 * This quest will show up before Reveille in the completed section of your quest log, even if you received it afterwards.
 * The Vertibird may not take off of the Cambridge Police Station roof, and Danse may talk as if the Vertibird is in the air. Using console command will allow the quest to progress.
 * If you complete Far Harbor missions prior to starting this quest then you will be unable to complete the "Speak to Lancer Captain Kells" object as the moment you approach the miscellaneous "Inform the BoS about the synth refuge" dialogue will automatically be triggered (trying to end that dialogue will just cause it to retrigger). Leaving the location and returning should fix it.

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