You brandish the weapon used in the spell’s casting and make a melee attack with it against one creature within 5 feet of you. On a hit, the target suffers the weapon attack’s normal effects and shadowy wisps of necrotic energy enshroud the target until the start of your next turn. If the target willingly makes a melee weapon attack against any other creature during the spell's duration, the target of this spell takes 1d4 necrotic damage and the creature being attacked by this target gains 1d4 temporary hit points, after the damage of this attack has been sustained, as the tendrils of dark energy transfer life essence from one to another, and the spell ends.

This spell’s damage increases when you reach certain levels. At 5th level, the melee attack deals an extra 1d8 necrotic damage to the target on a hit and the necrotic damage suffered by the target if they make a melee attack, as well as the temporary hit points gained by their target, increases to 2d4. All damage dice and temporary hit point rolls increase at 11th level (2d8 and 3d4) and 17th level (3d8 and 4d4).