Thunderous Strike

As an action, you can slam the knuckles together to unleash a thunderous wave. All creatures within a 15-foot cone must make a Constitution saving throw against your Spell Save DC. On a failed save, a creature takes 2d8 thunder damage and is pushed 10 feet away from you. On a successful save, a creature takes half as much damage and isn't pushed. After using this ability, it can't be used again until you complete a short or long rest.