Velkin's Striking Serpents

You magically create multiple spectral snakes that attack in a 15ft. cone. dealing 2d6 piercing damage. Additionally each creature within the 15ft. cone must make a Constitution saving throw. A target takes 4d6 poison damage on a failed save, or half as much on a successful one. 

At Higher Levels. When you cast this spell using a spell slot of 3rd level or higher, the poison damage increases by 1d6 for each slot level above 2nd.