Withering Smite

Your strike carries decay deep into the target's body. The target takes an extra 4d6 Acid or Poison damage (your choice).

The target must also make a Constitution saving throw. On a failed save, its Speed is halved, and it has Disadvantage on Strength and Dexterity saving throws until the start of your next turn.

Using a Higher-Level Spell Slot. The damage increases by 1d6 for each spell slot level above 3.