Arm Gyrojet (5e Equipment)
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Martial Ranged Weapons
An arm gyrojet is a concealable firearm worn on the forearm which fires gyroscopically stabilized .50 caliber rockets. The rockets are subsonic projectiles which, while still dangerously high-velocity, only make a quiet "hissing" sound when fired.
Special. Rockets fired from an arm gyrojet can be fired at either a creature or object or a point within range. A creature whose AC is hit by a rocket attack cannot attempt a saving throw to reduce the damage taken. Each creature within 5 feet of an exploding rocket 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.