Concussion Grenade

As an Action, you may throw a concussion grenade at a point up to 60 ft. away. Each creature within 20 ft. of an exploding concussion grenade must make a DC 15 Dexterity saving throw or become stunned until the end of its' next turn. Creatures
within 5 ft. of the grenade take 5d6 thunder damage. On a successful save, a creature takes half damage and isn't stunned.