Decaying Smite

As you hit the target, a plague of maggots and bacterial ooze begins to crawl across and infect its skin. It takes an extra 1d6 Necrotic damage from the attack and is Poisoned. At the start of each of its turns until the spell ends, the target takes 1d6 Nectrotic damage and then makes a Constitution saving throw. On a failed save, the spell continues. On a successful save, the spell ends. The target can use its action to clean the infection from its skin to end the spell.

Using a Higher-Level Spell Slot. The damage increases by 1d6 for each spell slot level above 2.