Big Boy is the upgraded version of Fatman Mini-Nuke launcher, it’s a unique weapon for you to get in Fallout 4, so here’s how and where you can find it for you to have a huge advantage while playing the game. Go to the Diamond City marketplace, first. At one side of the central building (it should be the left of the main entrance but it depends on where you are coming from) you will find Arturo.
He will be able to deliver as soon as you can pay it the Big Boy Mini-Nuke Launcher, but as we said it’s pretty expensive, coming at the cost of 10453 caps. The explosion deriving from this weapon is at least twice as big as Fatman’s, so it really looks like it is worth of that money. Check out our full Fallout 4 Wiki Page for more how to guides, tips and tricks, weapons, ammo and collectible locations and many other things.