Tempest

As an action, you toss up your feather and flourish your blade, creating a large tornado barreling down a 30 by 5 foot line. Each creature in the line must make a Dexterity saving throw. A creature takes 4d8 bludgeoning damage and is knocked prone on a failed save, or half as much damage and is not knocked prone on a successful one.

At Higher Levels. When you cast this spell using a spell slot of 5th level or higher, the damage increases by 1d8 for each slot level above 4th.