Glacial Monarch

Touched by ice, this sorcerer can trace their bloodline back to ancient monarchs of old. Subjugating entire kingdoms under their oppressive presence. Turn the battlefield into an inhospitable frozen wasteland. Freeze your foes in their tracks before they even reach you.

Monarch's Resolve

 As magic flows through you, it causes your body to adapt to the harsh nature of your origin. At the end of each short and long rest, you are cloaked in an icy layer of frost granting you temporary hit points equal to your Sorcerer level + Charisma modifier. While you have these temporary hit points your ac is increased by 2. 

As a permanent condition of this feature, you have resistance to cold damage and you and every item you wear and carry are unharmed by temperatures as low as -50 degrees Fahrenheit.

Cutting Northern Wind

At 6th level, you can emanate a wind whirling with snow. Before you cast a sorcerer spell of 1st level or higher you may stop restraining this aura until the end of your next turn.. When unrestrained, the 15 foot radius sphere around you is difficult terrain for all creatures except those of your choice. The wind moves with you, centered on you. at 18th level, the radius increases to 30 feet.

Sorcerous Blizzard

Starting at 6th level, when you cast a spell within your Cutting Northern Wind that deals a damage type other than cold you can change it to cold damage with 1 sorcery point.

When you cast a spell that deals cold damage  of 1st level or higher, your Cutting Norther Wind expands by 15 feet until the start of your next turn. At 18th level, it expands by 30 feet.

Permafrost

At 14th level, as a reaction when you or a creature within your Cutting Northern Wind are hit by an attack or fail a Dexterity saving throw, you can spend 1 sorcery point to reduce the damage taken by your sorcerer level + your charisma modifier (minimum of 1). 

Frozen Domain

Beginning at 14th level, over the course of one minute, you can choose an area of ice no larger than 150 feet on a side within 600 feet of you, or you can freeze an area of water of that size. You can reshape the ice in the area in any manner you choose. You can raise or lower the ice's elevation, create or fill a trench erect or flatten a wall, or form a pillar. The extent of any such changes can't exceed half the area's largest dimension. For example, if you affect a 150 foot square, you can create a pillar up to a 75 feet high, raise or lower the squares elevation by up to 75 feet, and so on. You can't shape the ice to damage a creature in the area, but you can shape it to trap them. Each 5 foot section of the ice has an AC and hitpoints equal to your sorcerer level.

Additionally, whenever you use this feature you may designate the area to be your Frozen Domain. Everywhere inside the 150ft radius located at the center of your selected area is considered to be under the effect of your Cutting Northern Winds. Over the course of a month the area affected transitions to a state of indefinite winter. Once you designate an Ice Castle, you cannot designate another one for 7 days. If you designate another, the previous one melts immediately.

Winter's Regal Armor

Starting at 18th level, you have gained a frozen heart and can don the attire of a winter monarch. You spend 6 sorcery points as an action to don Winter's Regal Armor. Its appearance is up to you, it replaces or goes over your present clothes, and only you can wear it. For 1 minute you gain the following benefits:

• You gain immunity to Cold Damage.
• Creatures who deal damage to you with a melee attack take your sorcerer level in cold damage.
• Creatures you kill with cold damage become petrified and stand as statues or shatter (your choice).
• Spells that deal cold damage gain bonus damage equal to your Charisma Modifier.

Once you use this feature, you can't do so again until you finish a long rest.