Corpse Explosion

You choose a pile of bones, or a corpse of a Medium or Small creature, within range and cause it to violently explode in a 10-foot-radius sphere. Each creature in that sphere makes a Constitution saving throw, taking 4d6 necrotic damage on a failed save or half as much damage on a successful one.

Using a Higher-Level Spell Slot. When you cast this spell using a spell slot of 3rd level or higher, you may target one additional corpse within range for each slot level above 3rd. The spell deals an additional 1d6 necrotic damage for each slot level above 2nd.