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Fallout 4: Defend the Castle - Build Defenses

Defend the Castle from the attack.

This guide will show you how to complete the Minutemen quest, Fallout 4: Defend the Castle. We’ll show you how to complete every single objective, and survive the attack by the Synths. Before you begin the quest, we advise that you equip some Power Armor, and the most devastating weapons that you have available to you.

Travel to the Castle

If you have completed all of the Minutemen quests before this one, you’ll be able to trigger this by simply traveling to the Castle. You should have a fast travel point unlocked to make this easier, but if you’re the hardcore type you can make the long journey from Sanctuary by foot.

Build Defenses

You’ll have to build up your defenses in order to complete this objective, but it should be fairly easy since your progress is tracked. You just need to get it to 100 percent. Our advice would be to use turrets to complete this, and more specifically, the kind that don’t use generators. The reason for this is that the Synths you’ll be fighting are going to target your generators, and the last thing you want to do is stop during battle to repair them. If you lack the resources to build up the necessary defenses, visit our Fallout 4 Base Building Guide for some tips.

Defend the Castle

As soon as you’re done with the previous objective, the Synths will begin to attack. You have a good chance to kill a few at distance if you have the right sniper rifle, as they’ll be approaching from a long way off. Try to thin them out a little to make the fight easier when things get messy in the Castle.

When the fight does get a little more up close and personal, switch to your most powerful weapons that can deal out damage quickly. We’re really big fans of the Overseer’s Guardian for this, ripping through the Synths like they aren’t even there. Of course, your Minutemen comrades and defenses will help, but you are going to be heavily depended on to deal some massive damage.

In all honesty, survival might be your most difficult task, not killing the Synths. For this we recommend that you either use some Power Armor, or that you always stay on the move and keep a good supply of Stimpaks ready to heal yourself up. Folks playing on the hardest difficulty are going to have the roughest time, of course, but this fight is winnable if you stay patient and minimize the incoming damage that you take. It also wouldn’t hurt to be rolling with your most lethal companion, so choose one that you think will give you the best chance at winning.

As you near the end of the fight, expect to battle several Institute Courser’s. They are very tough to kill, so hopefully you’ve brought all of your big guns. Also, remember to quick save as often as you can, that way you don’t have to do the entire fight over if you die, which you very well could.

Speak to Ronnie Shaw

When the battle is over, find and speak with Ronnie Shaw to complete this objective.

Talk to Preston Garvey

Preston should be at the Castle with you, so look for the objective marker on his head and speak with him. This will complete the mission, which might go down as one of the toughest to date.

If you’re ready to continue your journey with the Minutemen, you can move on to Fallout 4: The Nuclear Option (the Minutemen), or you can simply return to USgamer’s Fallout 4 Walkthrough and Guide, and then choose what you’d like to do next.

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