Waterball

Waterball
A bright surge of water streaks from you to a point you choose within range, then crashes with a deep roar into a swirling explosion of water and ice. Each creature in a 20-foot-radius sphere centered on that point makes a Dexterity saving throw, taking 8d6 cold damage on a failed save or half as much damage on a successful one.

Non-magical fires in the area are extinguished, and surfaces become slick with ice and water.

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