Cryomancy

Your magic is tied to a creature, being, or place that embodies the harsh and cold nature of ice. Perhaps you were abandoned in a blizzard as a child. Or maybe a frost giant, white dragon, or other creature with a strong tie to ice and snow raised you as one of their own. Regardless of how you gained this magic and what you choose to do with it, the very essence of ice flows within your veins—waiting for an outlet.

Source: GMBinder - FrostBladestorm, GMBinder - Rain-Junkie **I combined features from both to make a more personally ideal subclass** 

Frigid Magic

Starting at 1st level, you learn additional spells when you reach certain levels in this class, as shown on the Frigid Spells table. Each of these spells counts as a sorcerer spell for you, but it doesn't count against the number of sorcerer spells you know. Whenever you gain a sorcerer level, you can replace one spell you gained from this feature with another spell of the same level. The new spell must be a divination or an enchantment spell from the sorcerer or wizard spell list.

Frigid Spells
Sorcerer Level	Spells
1st	Armor of Agathys, Ice Knife, Frost Fingers
3rd	Rime's Binding Ice, Silence
5th	Hypnotic Pattern, Sleet Storm
7th	Freedom of Movement, Ice Storm
9th	Cone of Cold, Hold Monster

 

In addition, the Frostbite and Ray of Frost cantrips are automatically added to your spell list, and do not count against the number of spells you know.

Creeping Frost

Beginning at 1st level, your freezing spells chill your targets to the bone. When you deal cold damage with a sorcerer spell of 1st level or higher, you reduce the creatures speed by 10 feet. A spell that already reduces the targets speed increases the reduction by this amount. This feature can stack multiple times. This effect lasts for 1 minute after the final instance of cold damage, until the target takes fire damage, or until an effect would restore the creatures speed.

Glacial Steps

At 1st level, you can choose to freeze the ground where you walk as a Bonus Action. For the next minute, every 5-foot square you exit becomes glazed in ice and is treated as difficult terrain. Non-magical flames in the spaces you walk over are extinguished. Any water that you move through freezes and becomes solid ice that can support the weight of a Large or smaller creature. The ice caused by this feature lasts for 10 minutes, melting when it expires.

Once you use this feature, you can't use it again until you finish a long rest or you cast a spell of 1st level or higher that deals cold damage.

Frostborn

At 6th level, your affinity with ice empowers your defences. You gain resistance to cold damage, are unaffected by difficult terrain created by ice or snow, and are naturally adapted to cold climates as described in chapter 5 of the Dungeon Master's Guide. Additionally, when you finish a short or long rest, you gain a number of temporary hit points equal to your sorcerer level.

Coldsnap

At 14th level, the ice you create is harsh, and those who fall to your spells are infused with your cruel magic. When you reduce a creature that's small or larger to 0 hit points with a sorcerer spell that deals cold damage, it's dead body freezes solid and becomes an ice statue.

An ice statue is an object with an AC of 10 and a number of hit points equal to your sorcerer level. If its reduced to 0 hit points, it shatters harmlessly. It is frozen in the exact position of the creature that died. If any part of it is damaged or destroyed, the creature suffers similar deformities or injuries if it is later restored to life.

You can also spend 1 sorcery point as a bonus action to shatter a statue as long you can see it and it is within 60 feet of you. When an ice statue is shattered this way, all creatures within 10 feet of it must make a Dexterity saving throw, taking cold and nonmagical piercing damage equal to half your sorcerer level + your Charisma modifier on a failed save, or half as much on a successful one. That statue is then destroyed.

Absolute Zero

At 18th level, you can release primal, frigid magic that freezes anything it touches. As an action on your turn, you can spend 5 sorcery points to release this burst of freezing elemental power in a 60-foot radius, centered on you. Creatures of your choice in the radius must make a Constitution saving throw. On a failed save, the creature turns to ice, becoming subjected to the petrified condition. The icy form lasts for a minute or until the creature takes damage. The effect ends on affected targets if you use this feature again.

Additionally, any water or other harmless liquid in the radius is immediately frozen, and doesn't melt until it takes fire damage from a spell of 7th level or higher.