Blood boil

Blood Boil

3rd-level necromancy

Casting Time: 1 action

Range: Self (15-foot radius)

Components: V, S, M (a vial of blood)

Duration: Concentration, up to 1 minute

You draw forth the power of blood and death, causing it to boil within your veins. As an action, you can cause a wave of necrotic energy to pulse out from you in a 15-foot radius, affecting all creatures within range. Each creature in the area must make a Constitution saving throw. On a failed save, a creature takes 3d6 necrotic damage, and you regain hit points equal to the damage dealt. On a successful save, a creature takes half as much damage, and you do not regain any hit points.

If you concentrate on the spell for the full duration, the necrotic energy lingers, and at the start of each of your turns, each undead creature within the area gains temporary hit points equal to your proficiency bonus.

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. Additionally, the temporary hit points gained by undead creatures within the area increase by 5 for each slot level above 3rd.