This weapon must be crafted by the player, and requires the Mad Bomberperk to create.
Because the recipe requires normal mini nukes instead of the Gun Runners' Arsenal variations, there is a finite number of fat mines that can be created.
¹ Craftable without a workbench via a dialogue option with Veronica, or with ED-E once the add-on Lonesome Road is installed.
Notes
Only a normal mini nuke can be used for crafting. While this is not unusual, it is notable in that the majority of all vendor-stocked mini nukes are Gun Runners' Arsenal derivatives.
It is one of the heaviest placed explosives in the game; the only one that is heavier is Dead Money'sgas bomb, which weighs 1.75 pounds more than the fat mine.
Like many other home-made weapons, the fat mine's weight is not accurate when compared to the ingredients necessary to make it.
It inflicts substantially less damage than a normal mini nuke that is fired out of a Fat Man.
The fat mine has a very significant area of effect, much larger than any other placed weapon. As such, some advanced preparation is necessary to use a fat mine, similar to C-4 plastic explosives. Simply dropping a fat mine in front of an approaching enemy and running away will still result in the death of all but the most high-level players.
Like the gas bomb, the fat mine doesn't stay in place like other mines do because of its spherical shape, allowing it to roll forward or in other directions if placed on uneven ground.
Like most, if not all explosive mines, you can plant this on an NPC, and it will result in their pants exploding. However, considering the short delay and large blast radius, doing this is probably not a very good idea.
