Chaos Blackstorm

You channel the blackflame magic of old to create a searing storm of dark fire. Until the spell ends, searing fire bolts and cinders fall in a 20-foot-tall cylinder with a 40-foot radius centered on a point you choose within range. The area is heavily obscured, and nonmagical sources of light are extinguished. When a creature enters the spell’s area for the first time on a turn or starts its turn there, it must make a Constitution saving throw. A creature takes 2d8 necrotic damage and 4d6 fire damage on a failed save, or half as much on a successful one.

If a creature is concentrating in the spell’s area, the creature must make a successful Constitution saving throw against your spell save DC or lose concentration.