Darkening Smite

The next time you hit a creature with a melee weapon attack during the spell’s duration, Your weapon forms a black smokie aura around it, and the attack deals an extra 2d6 necrotic damage to the target causing it to form the same aura on its entire body. Additionally, if the target is a creature, it must succeed on a constitution saving throw or be paralyzed until the start of its next turn.