Blood Curse

You use the blood of the target creature to cause them harm. The target creature must make a Charisma saving throw. On a failed save, the target takes 5d10 necrotic damage, and cannot benefit from a long rest until the spell ends. A creature that succeeds in the saving throw takes half damage and cannot be targeted by the spell again for 24 hours. This spell has no affect on a creature with no blood.

At Higher Levels. When you cast this spell using a spell slot of 5th level or higher, the target takes an additional 1d10 necrotic damage and the duration increases by 1 day for each spell level above 5th.