Chilling Smite

The next time you hit a creature with a melee weapon attack during the spell’s duration, your weapon ignites with an ethereal frost. The attack deals an extra 1d6 cold or necrotic damage to the target and its speed is halved for the duration of the spell.

At the start of each of its turns until the spell ends, the target must make a Constitution saving throw. On a failed save, it takes 1d6 cold or necrotic damage (your choice) and its speed remains halved. On a successful save, the spells ends.

At Higher Levels. When you cast this spell using a spell slot of 2nd level or higher, the initial extra damage dealt by the attack increases by 1d6 for each slot.