You create a double-layered spell of ice and fire and throw it at a point you can see within range. Choose either fire or ice as the primary element:

• Primarily Fire. Creatures in a 15-foot-radius sphere must make a Dexterity saving throw, taking 6d6 fire damage on a failed save, or half as much damage on a successful one. Then the area becomes heavily obscured by smoke for 1 round.
• Primarily Ice. Creatures in a 15-foot-radius sphere must make a Constitution saving throw, taking 6d6 cold damage on a failed save, or half as much damage on a successful one. Creatures who failed the save are also pushed 5 feet away from the center by the rapidly expanding air.

Using a Higher-Level Spell Slot. The damage increases by 1d6 for each spell slot level above 3.