Thunder Punch

Your fist is empowered with thunderous force. Make a melee spell attack against the target. On a hit, a boom erupts from the impact that can be heard up to 50 feet away and the target takes 2d4 thunder damage. The target must also succeed on a Strength saving throw or be pushed 5 feet away from you.

The spell's damage increases by 2d4 when you reach 5th level (4d4), 11th level (6d4), and 17th level (8d4).  Additionally, the distance pushed increases by 5 feet when you reach 5th level (10), 11th level (15), and 17th level (20).