Thunder Strike

You brandish the weapon used in the spell's casting and make a weapon attack with it against one creature you can see within 5 feet of you. In addition to the attack's normal affects, you can cause all creatures in a 15 foot line in the direction of the target to fall prone or be pushed 5 feet away from you. If a creature in the line is huge or larger, they may make a Strength saving throw to resist being knocked prone or pushed, ignoring the affect on a success.

In addition to pushing or knocking creatures prone, all creatures within the 15-foot line take an additional 1d6 thunder damage at 5th level (1d6), 11th level (2d6), and 17th level (3d6)