Corrupted Divine Fireball

You create a small ball of Black Fire that quickly Grows as it takes flight high into the air. At its full size it begins to rain down Fire Bolts in rapid succession all flying toward a single point within range. Every target within a 20 Foot Radius sphere at the target Location must make a Dexterity saving throw. A target within this radius takes 14D6 Necrotic damage on a failed save, or half as much damage on a successful one. 

The fire spreads around corners. It ignites flammable objects in the area that aren't being worn or carried.

Azuth the god of Wizards once with the help of a powerful demon named Aartharn created an even more powerful version of fireball that delt radiant damage however Aartharn took the spell design and using his dark magic corrupted it creating the corrupted divine fireball.