Chastisement

4th-level evocation

Casting Time: 1 reaction, which you take when an ally you can see is hit by a melee attack

Range: 60 feet

Components: V, S

Duration: 1 minute

Divine wrath strikes a creature which harmed your ally. The creature must make a Wisdom saving throw. On a failed save, it takes 6d8 radiant damage and the next time it deals damage with a melee attack within 1 minute, its damage is halved. On a successful save, the target only takes half the damage.