The Fat Man MIRV launcher changes the Fat Man to launch six mini nukes simultaneously instead of just one, increasing the damage output of the weapon immensely. The mini nukes are initially clustered together after firing, but separate midair after mere milliseconds, similar to a cluster bomb. As a result, the effective range of the weapon decreases drastically, jeopardizing the user.
Nuclear material (6)
Gun Nut (4)
MIRV launcher (1)
This is a mod for the fat man, and can be found and used at any weapons workbench, if the player possesses the above materials.
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