Dead Again

When you cast this spell, choose one corpse or undead under your control within range. The target corpse or undead's soul is converted into fuel for an eldritch explosion. Each creature within 10 feet of the target must make a Dexterity saving throw. A creature takes 2d10 fire damage and 2d10 necrotic damage on a failed save, or half as much on a success. 

A corpse affected by this spell becomes a withered, empty husk, and cannot be affected by this spell again. 

An undead affected by this spell takes 40 force damage. If it is destroyed by this spell, it cannot be reanimated or affected by this spell again.

At Higher Levels: When you cast this spell using a spell slot of 4th level or higher, you can target one additional corpse or undead for each slot level above 3rd.