Firework quiver

Immediately after a hit ranged attack roll you may spend a bonus action to deal the damage of the attack +2d8 thunder damage in a 15ft cube centered on the hit target.
Other then the target all creatures in the cube may make a dc 15 dex save to take no damage.
Once you use this item, you cant use it again till next dawn.

Rarity

rare Wonderous item ( requires attunement)