You mastered the art of incorporating the icy power of the blizzard into your steps. Turning your presence on the battlefield into a flurry of blades and frost.

Steps of the Blizzard

From lvl 3 you learned the art of Snowdancing and gain proficiency in performance. If you allready have proficiency in performance you gain expertise. In addition you gain advantage to hide in snowy terrain and can hide if only lightly obscured, blending in with the landscape.

Hidden in the Blizzard

From 3rd level you can conjure up a wirling flow of snowflakes surrounding you within 5ft as a bonus action. You can use this feature up to proficiency modifier often, it recharges at the end of your long rest. This grants you half-cover. If you attack someone within your aura of frost you can use your sneak attack, even if you dont otherwise could not, as long as you do not have disadvantage on the attack roll and have not attacked with a two handed weapon this turn. In addition once per turn you can deal your charisma modifier in cold damage to an enemy entering or starting their turn within your aura as a reaction.

Frostmaidens Blessing

from 9th level you have imbued your very nature with that of the cold and freezing wastes. You gain resistance to cold damage, if you allready have resistance you gain immunity. In addition your attunement to the power of the blizzard has given you the ablity to enhance your deadly dance to new hights letting you cast Inflict wounds at will whenever your Frostmantle is active, replacing necrotic with cold damage. 

Call of winter

From 13th level your mastery of ice has led to adaptation to the allways surrounding cold. You dont need to eat, drink or breath. As an action you can encase yourself in ice to gain temporary HP equal to twice your level in this class. This feature can be used your proficiency modifier often per long rest. 

Grace of the Frostmaiden

From 17th level you have become an embodyment of the freezing cold as you peerlessly dance through the thundra of valikan. Once per long rest you can imbue your strikes with your frozen power. The next time you would use your Frostmantle feature it gains a range of 25ft and grants you heavy cover. Whenever you use your sneak attack feature winthin the range of your extended frostmantle you can choose to deal your sneak attack damage to additional creatures with in your frostmantle, up to equal your charisma modifier.