Blade of Bitter Cold

Blade of Bitter Cold. You smash the glaive to the ground and unleash a thin blade of ice in a 5 foot wide, 120 foot long line. Each creature in this line must make a DC17 Dexterity saving throw , taking 6d10 cold damage and gaining one level of exhaustion on a failed save, or half as much damage and no exhaustion on a successful one.