Your innate magic comes from the cold itself; perhaps you were born in an intense blizzard, or perhaps your birthplace was connected to Frostfell, the Para-Elemental Plane of Ice. However it came to be, the beauty and destruction of the cold has manifested within you, and you command its intense power.

Frostborn

When you choose this origin at 1st level, you become resistant to cold damage, you ignore icy difficult terrain, and you aren't affected by extremed cold.

Creeping Ice

Also at 1st level, all slow effects you create on a creature now stack. In addition, if you reduce a creature's movement to 0ft., it becomes frozen until it is hit by an attack or a spell; a frozen creature is considered restrained. A frozen creature can make a Strength saving throw at the start of each of its turns, ending the frozen condition on a successful save.

Heart of Frost

Starting at 6th level, your cantrips that deal cold damage ignore cold resistance. In addition, you can see creatures and objects that are lightly obscured by ice or snow as if they weren't obscured, and creatures and objects that are heavily obscured by ice or snow as if they were only lightly obscured.

In addition, your mere presence begins to cover the battlefield with chill winds. You gain an aura that extends 5ft. from you; all hostile creatures that start their turn in this aura are slowed by 5ft. until the end of your next turn.

Lingering Snow

Starting at 6th level, all of your spells of 1st level or higher that deal cold damage now also decrease the target's movement by 5ft. on a hit or a failed save; this effect ends at the end of your next turn. If the spell already slowed the target, it does so by an additional 5ft.

Encompassing Blanket

Beginning at 14th level, as an action, you can spend 3 sorcery points to increase your Heart of Frost's radius by 10ft. for 1 minute; for this minute, all hostile creatures that start their turn in it are slowed by 10ft. until the end of your next turn and take cold damage equal to your Charisma modifier (minimum of 1). You can use this feature a number of times equal to half your Charisma modifier (minimum of 1), and you regain all uses when you finish a long rest.

Snow Crash

Beginning at 14th level, as an action, you can spend 6 sorcery points to cause all frozen creatures within 100ft. of you to immediately lose the frozen condition and explode, taking 4d8 cold damage and then becoming vulnerable to cold damage for 1 minute. A creature that is resistant to cold damage loses that resistance for 1 minute instead.

Winter's Herald

When you reach 18th level, you become immune to cold damage, your Heart of Frost aura increases to a 10ft. radius, and all allies in your Heart of Frost aura count as adapted to extreme cold. In addition, while your Blanket feature is active, your speed is doubled when you take the Dash action on your turn. You also freeze water within this enhanced aura, allowing you to walk across it; it unfreezes as it exits your aura.

While your Encompassing Blanket feature is active, you can create structures out of ice within your aura, ranging from blocks to staircases. Such a structures lasts until your Encompassing Blanket feature ends, or until it is fully outside of your Encompassing Blanket aura, at which point it is dismissed. You may not create a structure in this way in a space that is occupied by another creature. You can use a bonus action to dismiss any or all of these structures. When such a structure is dismissed or destroyed, it crumbles into a pile of snow.