Flare Gun (5e Equipment)
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Simple Ranged Weapons
Normally used as a signaling device, a flare gun can be used as a weapon in a pinch. While colored flares are the only munitions that can reliably be used with a weapon with such poor recoil compensation, it wouldn't be impossible for smaller grenades to be made for them, though such a thing would most likely require more advanced technology.
Rather than being thrown at their normal range, the grenade is launched anywhere within this weapon's range before exploding. If you are firing within this weapon's long range, you must attempt a DC 15 Dexterity saving throw or fire the weapon 1d4 x 5 ft. away from the intended target in a direction determined by the DM.