Grenade, Stun (5e Equipment)
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Martial Ranged Weapons
Also known as flashbangs, thunderflashes, and sound bombs, stun grenades are intended to disorient combatants with a bright flash and a bang louder than 170 decibels.
As an action, you can throw a concussion grenade at a point up to 60 feet away. Each creature within 20 feet of an exploding concussion grenade must make a DC 15 Dexterity saving throw or become blinded and deafened until the end of its next turn. Creatures within 5 ft. of the grenade take 1d6 thunder damage. On a successful save, a creature takes half damage and isn't blinded and deafened.