atomic dragons blood Fireball

A dark streak flashes from your pointing finger to a point you choose within range and then blossoms with a low roar into an explosion of flame. Each creature in a 50-foot-radius sphere centered on that point must make a Dexterity saving throw. it deals 5d8 necrotic damage to each creature in the area + 8d8 fire damage that can be halved by a successful Dex save.

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

please note dragon borne do not need the vials of blood

At Higher Levels. When you cast this spell using a spell slot of 5th level or higher the damage increases by 1d8. every level above 9th you can cast an additional  dragons blood fireball (1 d6) for each slot level above 9th