Ulthar’s Soul Burn

You set fire to the very essence of a creature's soul. Choose one creature within range; it must make a Charisma saving throw. On a failed save, the creature takes 4d6 necrotic damage and is cursed with soul agony. For 1 minute, the creature suffers disadvantage on all ability checks and takes an additional 1d4 necrotic damage at the start of each of its turns.

At Higher Levels: When you cast this spell using a spell slot of 4th level or higher, the necrotic damage increases by 1d6 for each slot level above 3rd.