Boomerang Shield

Armor Magical Very Rare (this item requires attunement) [Monk]

While attuned this shield, you can throw the shield at a creature within 30ft of you as either an action or a bonus action. Make a ranged attack roll against the creature. If it hits the creature takes 1d6 bludgeoning damage and 1d4 force damage. If you roll a 20 on the attack, the creature must make a DC14 Strength Saving Throw or be forced backwards 10ft. After the shield is thrown and either collides with an object or reaches its maximum range, it will fly back until it has returned to you.