Baneful Strike

As part of the action used to cast this spell, you must make a melee attack with a weapon against one creature within the spell’s range, otherwise the spell fails. On a hit, the target suffers the attack’s normal effects, and you sap the creature's strength. Until the start of your next turn, the target must roll a d4 and subtract the number from the damage roll of its next weapon attack, then the spell ends.

The amount of damage subtracted from the damage increases at higher levels. At 5th level, 11th, and 17th level, the amount of damage subtracted increases by 1d4 points.