Brimstone Rain

A detrimental downpour of brimstone rains down unto the battlefield. This spell stretches in a 150 ft radius around the caster. Each creature in the radius will take 4d12 fire damage and 2d6 bludgeoning damage as they are pelted with pellets of brimstone. On the top of your turn, each creature in the radius will take the damage. 

This spell ignites all flammable objects in the radius, that isn't being worn or carried. Creatures cannot be invisible while in the radius.