Staggering Smite

Level: 4

Casting Time: 1 bonus action

Range: Self

Duration: Concentration, up to 1 minute

The next time you hit a creature with a melee weapon attack during this spell's duration, your weapon pierces both body and mind, and the attack deals an extra 4d6 psychic damage to the target. The target must make a Wisdom saving throw. On a failed save, it has disadvantage on attack rolls and ability checks, and can't take reactions, until the end of its next turn.

Source: PHB, page 278