's DLC introduces a number of mysterious factions across the foggy island map. There's the sour harbor folk, the secretive synths of Acadia, andthe radiation-worshiping cultists of the Children of Atom. The faction has appeared in other games previously, and even shows up in the Glowing Sea of, but they are present in Far Harbor with greater strength than ever, based in an old nuclear submarine.
The Children are currently led by Confessor Tektus, an aggressive zealot who wants nothing but death for the other folk on the island. But before him, another confessor led this group: Martin, a man only ever mentioned in the game when the player arrives. The mystery around Martin's disappearance, and the implications it has for the tensions on Far Harbor, are quite consequential when it comes to the DLC's core story.
While the Sole Survivor never meets Martin, he was, by all accounts, a kind and peaceful man. He is spoken of fondly by the Children of Atom and by the synths of Acadia, and even some harborfolk seem to think better of him than of his flock. He was the leader of the Children when they first came to the island, passing through the town of Far Harbor and picking up some new members before being kicked out. He met with DiMA, the head synth at Acadia, who gave Martin the old submarine to make his own.
The timeline concerning Far Harbor's history is never quite made clear, but it can be assumed that Martin's arrival took place over a decade ago, and his disappearance was within the past year or so.
While the Children accepted and befriended the synths, a schism would eventually form over the synth's building of Fog Condensers that dispelled the island's radiation. In addition, DiMa was hiding the location of the sub's nuclear launch key from Martin, though Martin himself seemed to be unsure about whether triggering the atomic payload would truly be the best way to help his followers. Tensions eventually reached a boiling point when a certain Child of Atom was killed
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