Blackmantle

Choose a 15-foot radius area within range. Any living creature within the area must make a Charisma saving throw, taking 2d10 necrotic damage on a fail, or half as much damage on a successful one. In addition, a creature that fails the saving throw is outlined with a dark aura and cannot benefit from any form of healing or regeneration for the duration. An affected creature can make another saving throw at the end of each of their turns, ending the spell’s effect on a success.