concertation breaker

the target must succeed in a constitution saving throw. On a failed save the creature can't cast a concentration spell until your next turn, and the creature takes 3d6 necrotic damage. on a successful save the creature takes half damage and they don't suffer the concentration debuff. also if the target is a spell caster concentrating on a spell, when they make the saving throw to maintain concentration the dc for the save is 15 or double the amount of damage they took.

At Higher Levels When you cast this spell using a spell slot of 3rd level or higher, the damage increases by 1d6 for each slot level above 2nd.