A dark streak of Necrotic energy flashes from your pointing finger to a point you choose within range and then blossoms with a low roar into an explosion of black flame. Each creature in a 20-foot-radius sphere centered on that point must make a Dexterity saving throw. A target takes 8d6 Necrotic damage on a failed save, or half as much damage on a successful one.
The dark fire spreads around corners but does not burn. Instead the Necrotic energy envelops the target and drains life energy from it.
On a failed save, you gain half the amount of damage taken as temporary hit points. You may only gain an amount of temporary hit points equal to your current hit point total and these are lost on a short or long rest. ON a successful save, target takes half damage and there is no life-steal effect.
At Higher Levels. When you cast this spell using a spell slot of 4th level or higher, the damage increases by 1d6 for each slot level above 3rd.
* - (A small piece of bone which is consumed by the spell, flint and steel)