Drain Vitality

1st-Level Necromancy (Void) (Wizard)

Casting Time: 1 action
Range: 60 feet
Components: V, S, M (a drop of blackened blood)
Duration: Instantaneous

You sap a creature’s ability to refresh itself through rest. Choose one humanoid you can see within range. The target must succeed on a Constitution saving throw or lose one Hit Die. A target of this spell that has no Hit Dice instead gains one level of exhaustion on a failed save. A target cannot gain more than one level of exhaustion in a day as a result of being targeted by this spell. The target that loses Hit Dice regains them at the usual rate upon finishing a long rest.

At Higher Levels. The target loses an additional Hit Die for each slot level above 1st used to cast this spell. A creature cannot lose Hit Dice and gain levels of exhaustion with the same casting of this spell.