SnowDancer

Within the blood of certain magical beings, dance great spirits of Winter. Free yet content, the power and wonder of these spirits seeps into the blood of the individuals they touch, instilling great magic, and, oftentimes, a love for performance. Sorcerers of this bloodline may have an ancestor who dances with the winter spirits, or they may have a spirit tied to themselves, spurring their movements and giving their magic a frosty fervor.

Your connection with the spirits of winter grants you a great affinity for winter's touch. Among other features learned at later levels, you gain a new spell each time you gain a new feature with this class. You learn the Frostbite cantrip at level 1, the Wall of Ice Spell at level 6, the Freezing Sphere spell at level 14, and the Cone of Cold at level 18. These spells are Sorcerer Spells for you, and do not count against your list of spells known.

Winter Wonder

Your deep connection with the spirits of winter allows you to dance in tune with their fluid movements. When you choose this bloodline at level 1, you gain proficiency in performance checks requiring you to dance, and cold weather is not harmful for you.

Additionally, as an action on your turn, you may begin a special Snow Dance that lasts for up to 1 minute. During this time, your fluid movements cause thin layers of frost to flow around your body, granting you a higher level of resistance. While dancing, you gain a bonus to your AC equal to your charisma modifier as well as advantage on Dexterity and Charisma Saving throws, but your movement speed is reduced by half, and sorcery point costs are doubled. This effect does not require concentration, but if you suffer any form of damage, you must roll a Constitution saving throw as if you were holding concentration. Being knocked prone by any means stops your dance and ceases the effects. 

You may use this feature a number of times equal to your Charisma Modifier, and regain all uses with a Long Rest. 

Frigid Flamenco

Upon reaching level 6, Curtains of fierce, frigid wind whip around you as you continue your dance, biting at your enemies and sapping them of their strength. While you dance, enemies within a 45ft radius lose their cold resistance, and any enemies with cold immunity instead take half damage from spells that deal cold damage. These winds also protect your allies, granting them cold resistance while they stay within 20ft of you. You remain unaffected.

Additionally, whenever you cast a spell during your snow dance that deals cold damage, you may add your charisma modifier to the damage dealt.

Blizzard Bolero

At level 14, Drives of harsh snow and sharp ice swirl around you quickly as you dance. When creatures enter or begin their turn within the radius of your Snow Dance, they must make a Dexterity saving throw or take 3d8 cold damage. The Area your Snow Dance Covers is considered Rough Terrain for all creatures without cold resistance.

Additionally, any projectile that is fired through your dance's area of effect now has a severe chance of being blown off course. Reduce the damage of all projectiles fired through this area of effect by a number equal to your character level. If the damage is reduced to zero, the projectile is blown off course and misses completely.

Glacier Fouetté

When you reach level 18, the bitter cold brought forth by your Snow Dance is even more dangerous to your enemies that remain close. Creatures without cold resistance that end their turn within it's area of effect must make a a Constitution saving throw against your Spell Save DC or be petrified until your Snow Dance ends. The Creature is encased in magical ice that grants resistance to all damage that isn't magical fire damage, and it is immune to cold damage altogether.