The next time you hit a creature with a melee weapon attack during the spell’s duration, your weapon inflicts a wound, and the attack deals an extra 1d6 necrotic damage to the target. At the start of each of its turns until the spell ends, the target must make a Constitution saving throw. On a failed save, it takes 1d6 necrotic damage. On a successful save, the spell ends. If wounded creature regains any hit point from a magical effect or a similar healing effect (such as a use of a healer's kit), the spell ends.

At Higher Levels. When you cast this spell using a spell slot of 2nd level or higher, the initial extra damage dealt by the attack increases by 1d6 for each slot.