You choose a point within range and cause all the warmth to vanish from its vicinity. Each creature in a 20-foot-radius sphere centered on that point must make a Constitution saving throw. A target takes 4d8 cold damage on a failure, or half as much damage on a success.   If a creature fails the saving throw, it is frozen in place, locked down by sheets of ice. It takes 1d8 cold damage at the start of each of their turns, and is restrained. It may reattempt the saving throw at the end of each of their turns, ending the effect on a success.