Heliana's Guide to Monster Hunting, pg. 509
2nd ring Primordial, Necromancy
You summon a bolt of negative energy to stimulate and transmit necrotic pathogens into those that stand before you, decaying their internal viscera. Each creature in a 5-foot-wide, 50-foot-long line extending from you must make a Dexterity saving throw, taking 3d8 necrotic damage on a failed save, or half as much damage on a successful one.