Aspect of the Crucible: Tail

You create a flexible tail and swing it in a wide arc around you. You can choose to target creatures in either a 10-foot radius or a 20-foot radius around you.
Each target in the area must make a Dexterity saving throw or take 6d6 bludgeoning damage. Creatures that are Large or smaller fall prone when they fail the save.
At Higher Levels.
When you cast this spell using a spell slot of 4th level or higher, the damage increases by 1d6 for each slot level above 3rd.