Crystal Breath

Sorcery developed by Myridin Emrydis during his infatuation with the Crystal Spheres. Emit crystal breath of an Astral Dragon.
Although it no longer causes curses, what madness caused old Big Hat Emrydis to appropriate this frightful power of the ancient dragons?

A line of jagged crystal 90 feet long and 5 feet wide emanates from you in a direction you choose. Each creature in the line must make a Dexterity saving throw. A creature takes 10d10 + 50 slashing damage on a failed save, or half as much damage on a successful one.