機械守衛

	關於the holodisk game，參見Automatron (holotape)。關於the customizable companion，參見Automatron (companion)。

機械守衛

“	The mysterious Mechanist has unleashed a horde of evil robots into the Commonwealth, including the devious robobrain. Hunt them down and harvest their parts to build and mod your own custom robot companions. Choose from hundreds of mods; mixing limbs, armor, abilities, and weapons like the all-new lightning chain gun. Even customize their paint schemes and choose their voices!	”
—Official description

機械守衛是Fallout 4第一個擴充內容 , 於2016年3月22日發售。玩家建議等級15。

內容

故事講述機械大師正在聯邦打算使用機器人一統聯邦，而你正前往無線電來源幫助機器人艾達並一起解開機械大師之謎。

此DLC新增機器人的工作檯，可以用來改造艾達、嘎爪、居禮（限還是幫手小姐時），並且可以創造屬於玩家自己的機器人。

另外增加新的掠奪者陣營：鐵鏽惡魔。

Installing the add-on adds a couple of new idle comments to most companions' repertoire. These lines revolve around robots and let the Sole Survivor's followers express their opinion of the machines in various ways depending on personality. If an automatron built by the player character shares a settlement with an organic companion or is currently traveling with the Survivor, their updated comments tend to make up the majority of their idle chatter when they get within earshot.
Similar to above, a small number of new loading screens are added to the basic ones as soon as Mechanical Menace is started in earnest. They seem to replace the normal loading screens almost completely even after the Automatron questline has been finished, severely limiting the overall choice of loading screens one gets to see.