Avenberry's Absolute Zero

A bright streak flashes from between your swirling hands to a point you choose within range and then blossoms into a translucent shell of ice which removes all heat from inside it before shattering inward. Each creature in a 20-foot-radius Sphere centered on that point must make a Dexterity saving throw. A target takes 6d6 cold damage on a failed save, or half as much damage on a successful one.

The ice does not spread around corners. If a creature in the area is reduced to zero hp they must also make a Constitution saving throw (DC 10), or shatter.

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.At Higher Levels.