Void Bomb

A spot of purple flame flashes from your hand toward the desired location and explodes into a sphere of void fire. Each creature in a 20-foot radius must make a Constitution saving throw, taking 8d6 necrotic damage on a failed save and half as much on a successful one.

The fire spreads around corners. It ignites flammable objects in the area that aren't being worn or carried. It also destroys any non magical rubble in its area.

At Higher Levels. When you cast this spell using a spell slot of 4th level or higher, the damage increases by 1d6 for each slot level above 3rd.