Corpse Burst

When an undead you can see within range dies, you can disperse the last of its lifeforce into a burst of Necrotic and Radiant energy. Every creature within 10ft. of the corpse must make a Dexterity Saving Throw. On a failure, the target takes 4d6 Necrotic or Radiant damage (or half it up with 2d6 of each). On a success, the creatures take half damage of the damage type chosen.