In a sudden flash, you instantly freeze the air around a creature in range. The target must make a Constitution saving throw, taking 2d6 cold damage on a failed save, and half as much on a success. If the target already took cold damage on your turn, it has disadvantage on the saving throw.   If the target fails the saving throw, it becomes paralyzed for 1 round, or until it takes damage. While paralyzed this way, the target is vulnerable to fire and bludgeoning damage, as well as damage from the spell Shatter.