Big Boy

The Big Boy is a unique weapon in Fallout 4.

Characteristics
The "Big Boy" is a Legendary Fat Man with the Two-Shot Mod, allowing it to shoot two mini nukes at once for the cost of only one, giving it the most damage potential from a single shot in the entire game.

The Big Boy is compatible with the Experimental MIRV mod; the Big Boy will shoot an astounding sixteen mini-nukes, while only consuming one. Be aware that the blast radius from shooting this is substantially larger than normal. (Wrong ! Tested on PC 28/11/15, the two "groups" of two Mini Nukes divided into 10 bombs in total (5 per "group" of two nukes), not 16. I captured a video of a launch and paused to verify it, either with a MIRV Big Boy or a console generated Fat Man with the same legendary mod + MIRV Mod.)

Variants

 * Fat Man

Locations
Can be bought from Arturo in the Diamond City market.