Deep Magic Volume 2 (p.204)
Ominous Shadow
6-level Necromancy
Casting Time: 1 action
Range/Area: Self (60 ft. cone)
Components: Verbal, Somatic, Material
Materials: a horn from a creature native to the Plane of Shadow
Duration: Instant
Attack/Save: CON Save
Damage/Effect: Necrotic
When you cast this spell, you extend your shadow out in a 60-foot cone. Each creature in the area must make a Constitution saving throw. On a failed save, a creature takes 8d10 necrotic damage and has disadvantage on attack rolls and saving throws until the end of its next turn. On a success, a creature takes half the damage and doesn’t have disadvantage on attack rolls and saving throws from this spell.
At higher levels: When you cast this spell using a spell slot of 7th level or higher, the damage increases by 1d10 for each slot level above 6th.
Available for: Sorcerer, Warlock, Wizard