There is a way in Fallout 4 using which you can get Unlimited Fusion Cores. For those who are unaware of, Fusion Cores are needed to use Power Armor in Fallout 4. The guide below gives you detail regarding a BoS soldier from who you can STEAL Unlimited Fusion core.
The BoS soldier shown in the screenshot below respawn a new full fusion core whenever you steal one from him giving you essentially a limitless supply of fusion cores. He is guarding the entrance to the long Hallway at Boston Airport. To those who want to know the whereabouts of Boston Airport on the map: There’s an underground route at a location named Swan’s Pond. There are just few easy enemies in the area. You’ll need to look underwater for it, so make sure to pick off any of the low level creatures in the water.
Minor Spoiler ahead for those who want more details: There is a super mutant behemoth sitting completely under the water with a swan boat attached to his back, which looks like its floating on the water. He’s friendly until you enter the water. You can very easily kite him around the fence to kill him.
Tip on how to kill this super mutant behemoth: On the Southwest corner there is a raider camp, just get up on the scaffolds and then you only have to dodge the rocks he throws at you. He can’t reach you.
Here is another location in Fallout 4 where you can get a total of 8 Fusion Cores. I have mention below just the location, go ahead and read it, there is no story spoilers.
The location is Weston Water Treatment Plant. Use the elevator, to the left is a locked door, novice I think, behind it are some ammo boxes. I have 1 point in scrounger and I found 4 full power fusion cores in each ammo box. The treatment plant is on the river east of Fiddler’s Green . Or south or ArcJet.
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