Drakkor's Blast of Ice

A pale blue streak flashes from your pointing finger, or focus, to a point you choose within range and then blossoms with a high pitched roar into an explosion of ice.  Each creature in a 20-foot-radius sphere centered on that point must make a Constitution saving throw.  A target takes 5d6 cold damage on a failed save, or half as much damage on a successful one.  On a failed save, that creature also has its movement reduced by 10 feet until the end of the caster's next turn.

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