You can solve the conflict amicably, without losses, or you can destroy one of the conflicting parties, you can destroy the two conflicting parties, or you can leave behind only smoking ruins on the island.
How to resolve this conflict is up to you. Initially, the protagonist comes to the island to find the girl Kasumi, who for some reason considered herself a Sint and ran away to Acadia, but eventually the protagonist finds himself caught up in the conflict between these three factions. The island has a village called Far Harbor, a fanatic sect base called Children of the Atom, and a Sint settlement called Acadia. The Fallout 4 Far Harbor add-on adds a large island to the game, on which all events unfold.
New weapons, armor, and clothing (over 50).A new huge island, which has 58 different locations where all the action takes place.