Glacial Storm
A blizzard descends on a 40-foot radius. Each creature in the area makes a Constitution saving throw against your spell save DC. On a failure it takes (H + half your level)d8 cold damage and its Speed is halved for 1 minute; on a success it takes half damage and is not slowed. A slowed creature repeats the saving throw at the end of each of its turns, ending the effect on a success.
Speed halved: the creature moves at half its usual rate, and its Speed cannot be restored while the effect lasts.
All water in the area freezes solid. A creature that moves across the frozen ground makes a Dexterity saving throw against your spell save DC or falls Prone.
If a suitable corpse is nearby, raise a large Frost Golem under the coven's control. HP Hd20+10, AC 14, immune to cold, vulnerable to fire.

