Toxic Breath

You unleash a cloud of misty black or green vapor. Each creature in a 30-foot Cone originating from you makes a Constitution saving throw, taking 6d6 necrotic damage on a failed save or half as much damage on a successful one. A creature that fails the saving throw by 5 or more also erupts into a fit of spontaneous vomiting, causing them to become [condition]incapacitated[/conditon] until the end of their next turn.

Using a Higher-Level Spell Slot. The damage increases by 1d6 for each spell slot level above 5.