Apoptosis

You unleash a focused blast of necromantic energy upon a single creature; damaging the cellular structure of your target. Make a ranged spell attack against your target. A creature hit by this spell takes 2d6 fire damage and 4d10 necrotic damage. A creature killed by this spell explodes, sending organic shrapnel out in a 20 ft sphere. Each creature in this sphere must make a dexterity saving throw or take 2d10 necrotic damage.

At Higher Levels. Target one additional creature for each spell slot above 4th level, up to a maximum of 3.