Wave Of Calamity
Tier 1 Epic necromancy
Casting Time: 1 action
Range: Self (30-foot cone)
Components: V, S, M (demon bile)
Duration: Instantaneous
Toxic fumes emanate from your mouth. Each creature in a 30-foot cone must attempt a Constitution saving throw. A creature gains two levels of exhaustion on a failure, or one level on a success. A creature with one or more levels of exhaustion gained from this spell may attempt a Constitution saving throw at the start of each of its turns to remove one level of exhaustion gained from this spell. A creature immune to the poisoned condition has Epic advantage on saving throws against this spell.
At Higher Levels. When you cast this spell as a tier 2 Epic spell or higher, a creature gains two additional levels of exhaustion on a failed saving throw per tier above tier 1, or half as many levels on a success.
Ref: ELCR p106