Crimson Slaughter

You fuel your strikes with supernatural killing power. Make a melee spell attack against a creature within range. On a hit, they take 8d10 necrotic damage, and if this reduces them to 0 hit points, their corpse explodes in a 10-foot radius blast of blood and bone. Each creature in the area must make a Dexterity saving throw, taking 4d10 necrotic damage on a failed save or half as much on a success.

At Higher Levels: When cast using a spell slot of every other level, the primary necrotic damage increases by 1d10, and the explosion damage increases by 1d10 for every slot level above 5th.