Complete the Mass Fusion quest from the Institute. Continuation of Institute and Railroad quests You can load the game from before you started Mass Fusion quest from the Institute. By now, you should have unlocked all Minutemen and Brotherhood of Steel achievements (the remaining ones are from Railroad and Institute). It's one of the endings and completing it will give you an achievement. Complete quests for the Brotherhood of Steel until you unlock The Nuclear Option. You will become a member of this faction at the end of Call to Arms quest.

Start completing the Brotherhood of Steel quests. Your first one might be either Reveille (meeting the members of the Brotherhood on the Boston airport) or Fire Support (offering support to the Brotherhood of Steel members fighting near the police station in Cambridge).

It's a crucial step since completing the quest will turn you into an enemy of the Brotherhood of Steel and you won't be able to complete other quests from this faction. SAVE THE GAME MANUALLY before you begin the next quest - Mass Fusion. During The Battle of Bunker Hill, you can behave in any way you want towards the synths that you find, because this decision does not deteriorate your relationships with any of the factions to the point where you become their enemy. Complete three initial quests for the Institute - Synth Retention, The Battle of Bunker Hill and Mankind Redefined. Don't worry, it won't stop you from cooperating with any other faction. While performing this task, agree to work with the Institute - the fourth faction in the game. After completing The Molecular Level, a main quest called Institutionalized will begin. Main quest 'Institutionalized' and first Institute quests Make progress in it as far as you currently can.

Ask the Railroad for help - it will trigger the Underground Undercover quest. The game will suggest you to get help from one of the factions. Go back to completing The Molecular Level. Complete their first two quests - Road to Freedom (first Railroad encounter) and Tradecraft. While completing The Molecular Level you will be forced to contact the Railroad faction. Start with completing the main quest called The Molecular Level. Main quest 'The Molecular Level' and first Railroad quests Completing this would prevent you from completing other main quests that offer achievements. Do not help the towns (random quests) because it will lead to the Minutemen ending (defense of the Castle, one of their towns). When you complete Old Guns DO NOT CONTNUE performing tasks for Minutemen. Complete Minutemen quests up until the end of Old Guns. Complete the main quests up until the end of Hunter/Hunted. While taking care of these tasks, do not begin ones related to the Brotherhood of Steel or the Railroad. From this point, you will be able to complete main quests and Minutemen ones interchangeably, or focus on one group of quests at a time. At the and of Out of Time you will encounter the Minutemen for the first time and their quest called When Freedom Calls will begin. Start with completing two of the first main quests - Prologue and Out of Time. If you haven't made wrong choices in the essential moments, you should be able to continue the process of unlocking achievements. Don't worry if you did something slightly differently. Note - The proposed list is not the only way of unlocking every achievement (and a platinum trophy on PlayStation 4). You can't miss it and you may take care of them with no difficulties. Note - Achievements unrelated to quests and important choices were not included in the list below. The description of all main quests and faction missions can be found in the walkthrough part of our guide. If you do not wish to get all of the achievements, complete the game however you wish and, for example, commit to your favorite faction. It is not the best way to interact with the game because you will be forced to skip some quests, e.g. Note - The list below concerns playing the game just to unlock every possible achievement. They assume only basic cooperation with factions in a specific order, and saving the game in several vital moments. Luckily, you do not need to start the game all over again and use the tricks shown below. Moreover, Fallout 4 has several endings that are mutually exclusive. Your cooperation with faction A might have a negative impact on the relations with faction B or even make you their enemy. Unlocking all of the achievements in a single playthrough is not an easy job to do in Fallout 4.It is so because of conflicting interests of four factions in the game.

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