In Fallout 4 , players must decide the fate of the Commonwealth by siding with one of four competing factions. Each faction holds a certain ideology with regard to the fate of the Commonwealth, and in this Fallout 4 Best Ending guide we'll walk you through the steps to take in order to get the best ending in Fallout 4. If you were instead after how to get the best ending for Fallout 4: Far Harbor, then head over to out Fallout 4 guides walkthrough hub , containing a wealth of information on quests, areas, and the best items in the game. After Act II, players must choose which faction they would like to support.