Thandar’s Storm of Cards

Crackling spectral cards whirl out from you in a violent storm. Each creature of your choice within 15 feet of you must make a Dexterity saving throw. On a failed save, a creature takes 6d8 force damage and 6d8 lightning damage and is pushed up to 10 feet away from you. On a successful save, the creature takes half as much damage and is not pushed.

The area within 15 feet of you is filled with these spectral cards for the duration. The area is difficult terrain for creatures other than you. When a creature other than you enters the area for the first time on a turn or starts its turn there, it must make a Dexterity saving throw. On a failed save, it takes 3d8 force damage and 3d8 lightning damage and is pushed up to 10 feet in a direction of your choice. On a successful save, it takes half as much damage and is not pushed. A creature can be affected by this secondary effect only once per turn.

The storm moves with you, remaining centered on you for the duration.

At Higher Levels. When you cast this spell using a 9th‑level spell slot, both the initial and secondary damage rolls increase by 1d8 force and 1d8 lightning. The area also increases by 5.