Panzerknacke (5e Equipment)
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Martial Ranged Weapons
This oddity of a weapon is allegedly a recoilless, electrically fired 30mm wrist cannon, designed by Germany in WWII to be used as part of an exceptionally bizarre plot to assassinate Stalin. It never saw any recorded use, and whether it even existed at all or was just a hoax is up for debate.
Special. Shells fired from a panzerknacke can be fired at either a creature or object or a point within range. A creature whose AC is hit by a shell attack cannot attempt a saving throw to reduce the damage taken. Each creature within 10 feet of an exploding shell must make a DC 15 Dexterity saving throw, taking the listed damage on a failed save, or half as much damage on a successful one.