You summon the raw power of winter itself, unleashing a cataclysmic frost across the world. As you initiate this spell, a bone-chilling aura surrounds you in a 200-foot radius sphere, engulfing the nearby terrain.

Each creature within the area of effect must make a Constitution saving throw. On a failed save, a creature takes 12d10 cold damage and its speed is reduced to 0 until the end of its next turn. On a successful save, the creature takes half damage and suffers no speed reduction.

The freezing effect extends to the terrain, causing difficult terrain for the duration of the spell. In addition, any non-magical flames in the area are extinguished, and all water within the sphere instantly freezes.

Creatures that start their turn within the area of effect must repeat the saving throw. Additionally, at the end of each of your turns while concentrating on this spell, the affected creatures take 5d10 cold damage.

While this spell is active, you may use a bonus action to move the sphere up to 30 feet in any direction. The sphere must remain within range, and any creature inside its area of effect must make the saving throw as appropriate.