Diamond Dust

You coalesce a large mote of freezing magical energy and blast it forward forming a line 100 feet long and 5 feet in a direction you choose. Each creature in the line must make a Dexterity saving throw. A creature takes 4d6 cold damage and 4d6 piercing on a failed save, or half as much damage on a successful one.

At Higher Levels. When you cast this spell using a spell slot of 4th level or higher, the cold damage increases by 1d6 for each slot level above 3rd.