Plague Spirit

Decrepit Mist. A cloud of green mist with a diameter of 1 mile and height of 60 feet is centered on the spirit. For each day a creature spends in the mist, it must succeed on a DC 16 Constitution saving throw or increase in age by 5 percent of its total life span. The mist has no effect on undead or constructs.

Hunter of the Living. The plague spirit can magically sense the general direction of the largest concentration of living flora and fauna within 50 miles of it.

Multiattack. The plague spirit makes three attacks: one with its enfeebling touch and two with its censer.

Censer. Melee Weapon Attack: +8 to hit, reach 10 ft., one target. Hit: 13 (2d8 + 4) bludgeoning damage plus 7 (2d6) necrotic damage.

Enfeebling Touch. Melee Weapon Attack: +8 to hit, reach 5 ft., one creature. Hit: 14 (4d6) necrotic damage, and the target's Strength score is reduced by 1d6. The target dies if this reduces its Strength to 0. Otherwise, the reduction lasts until the target finishes a short or long rest.

Dance of Death (Recharge 5-6). The plague spirit dances and twirls its censer. Each creature within 20 feet of the plague spirit that can see it must make a DC 16 Constitution saving throw. On a failure, a creature takes 28 (8d6) necrotic damage and is frightened for 1 minute. On a success, a creature takes half the damage and isn't frightened. A frightened creature can repeat the saving throw at the end of each of its turns, ending the effect on itself on a success.