Bestow Plague

You summon a plague able to kill entire towns. Choose any number of creatures up to 10,000 creatures. Each one of these creatures must make a Constitution saving throw. On a successful save, the creature takes 6d4 necrotic damage and is stunned. On a failed save, the creature becomes infected with the plague. The creature loses 12d4 hit points (1d4 hit points lost for every 2 hours) and gains a level of exhaustion (No level of exhaustion on the first day of being infected) per day they are infected.

Any healing spell above 4th level has a chance of curing a single creature of the plague (or more if the spell targets multiple people). The caster of the spell must succeed on a spell attack roll against a DC of 25 (The DC decreases by 3 for each spell level above 4th. Ex: A 6th level healing spell has a DC of 19). This also applies to bringing a creature back to life who has died due to the plague.