Thunderstrike

With a mighty crack, your weapon thuds into the ground, transmitting thunderous energy towards a creature within range. Make a melee spell attack against the creature, dealing 3d8 bludgeoning damage and knocking it prone as the ground beneath the creature juts upward in proportion to the force of the blow.

The creature chosen must be in contact with solid ground for this spell to work; the spell cannot extend across any change in elevation greater than 10 feet.

At Higher Levels. When you cast this spell using a spell slot of 2nd level or higher, the damage increases by 1d8 per slot level over 1st.