Choose  a creature of your choice that you can see within range. You mark his soul with dark energy. the creature takes 2d8 necrotic damage when you cast the spell. Until the spell ends, you can use an action or bonus action on each of your subsequent turns to cause this damage again.

The creature can perform a Wisdom saving throw. if the saving throw is successful, the effect ends.

At Higher Levels. When you cast this spell using a spell slot of 3rd level or higher, the damage increases by 1d8 for each slot level above 2nd.