Chaos Storm

You summon forth demonic fire and lava from the earth that engulfs the area around you in a 30 foot radius. Creatures in the area must make a Constitution saving throw or take 18d10 fire damage and be knocked prone, or half as much damage and not knocked prone on a successful save. Objects and plant creatures fail the saving throw automatically and take maximum damage.

The ground in this area remains hazardous until the end of your next turn: creatures other than you that start their turn there or enter the area for the first time take 2d10 fire damage.