- Speaking with Father, it is revealed that a rogue synth had undergone a memory wipe, instigated by The Railroad, and has now begun terrorizing the Commonwealth in his new personality, as a ruthless raider leader in command of the raider town of Libertalia.
- Upon arrival at the Nahant township, the Sole Survivor will need to team up with an Institute courser under the designation X6-88, the same courser seen in Kellogg's memories, who will help cleanse the raider town of all life.
- After making it onto the upturned cruise ship (beware the raider utilizing a Fat Man, who is overseeing the elevator leading up onto the ship), serving as the town's command center, the party will need to fight their way upwards, until finally reaching the captain, the rogue synth, Gabriel, and two raider lieutenants.
- Just before entering the area where the rogue synth presides, X6-88 will reveal to the Sole Survivor that Gabriel can be taken down peacefully by speaking his code phrase. Regardless of whether the code phrase is used in the next area, Gabriel will be knocked unconscious, and X6-88 will thank the Sole Survivor before teleporting back to the Institute with Gabriel.
- Return to the Institute, and speak with Father, who will then grant the Sole Survivor their own personal quarters within the Institute.
|Talk to Father|
|Meet up with the Courser||Shaun asked me to help reclaim a rogue synth who's taken over a raider gang. I'll meet up with a Courser at Libertalia to begin the mission.|
|Reclaim the Rogue Synth||Shaun asked me to help reclaim a rogue synth who's taken over the raider gang at Libertalia. I've joined forces with a Courser named X6-88, and together we'll confront the raiders and bring the synth home.|
|Return to Father||Shaun asked me to help reclaim a rogue synth who's taken over the raider gang at Libertalia. Now that the synth has been returned to the Institute, I need to tell Shaun that the mission was a success.|
|Visit Your Quarters||The mission to reclaim the rogue synth at Libertalia is over, and Shaun has asked me to visit the personal quarters he had prepared for me. He said that I would find a stock of useful supplies waiting for me there.|