Boulder Hew

You ripple and tear at a large area of stones, shaping it into a rough 10 feet wide and 10 feet long circular stone boulder! Choose a targeted location within range. All creatures within 20 feet of the boulder`s impact must make a DC (8 + casters proficiency bonus + casters casting ability modifier) Dexterity saving throw, suffering 7d8 bludgeoning damage. Succeeding the saving throw causes only half damage. Once the Boulder hits the ground, the rubble that is left will create a 20 ft radius of difficult terrain.

Boulder Hew counts as siege damage against buildings.

At Higher Level. Increases the damage by 1d8 for each spell slot above 4th level.