Frost Knight

Somewhere in your lineage your bloodline was effected by dark wild magic while traveling in the northern snow covered wastes . It stained your line and has finally emerged. Your form becomes gaunt and takes on the visage of death but becomes cold as ice and tough as the earth itself.

Rime

At 3rd level you gain Resistance to Cold damage and your attacks do additional Cold damage equal +2 at 3rd, +3 at 9th,and +4 at 16th.
At 5th level you gain +1 Armor Class.

Frost Squire

You may cast the Animate Dead spell twice per long rest.
Whenever you create an undead in this way, it is considered a Frost Squire and has additional benefits:
The creature’s hit point maximum is increased by an amount equal to twice your fighter level.
The creature adds your proficiency bonus to its armor class, weapon attacks, and weapon damage rolls in cold damage.
The creature also has resistance to cold.

This spell creates a Frost Squire. Choose Medium or Small humanoid. The spell summons a skeleton Frost Squire wreathed in Ice at your command.

On each of your turns, you can use a bonus action to mentally command the Frost Squire if it is within 60 feet of you (if you control multiple Frost Squires, you can command any or all of them at the same time, issuing the same command to each one). You decide what action the Frost Squire will take and where it will move during its next turn, or you can issue a general command, such as to guard a particular chamber or corridor. If you issue no commands, the Frost Squire only defends itself against hostile creatures. Once given an order, the Frost Squire continues to follow it until its task is complete.

The Frost Squire is under your control for 24 hours, after which it stops obeying any command you've given it. To maintain control of the the Frost Squire for another 24 hours, you must cast this spell on the creature again before the current 24-hour period ends. This use of the spell reasserts your control over up to four Frost Squires you have animated with this spell, rather than animating a new one.

Ice Walker

Allies withing 10 Ft of you gain Resistance to Cold damage. Additionally, you and allies with 10 feet may also pass over ice and water as if it were ice and through magical and non-magical plants without being hampered or slowed by them, without taking damage from them if they have thorns, spines, or a similar hazard.

Icing Death

Beginning at 15th level, you gain Resistance to Necrotic and Poison damage. Also your Critical Strikes do additional Cold, Necrotic and Poison Damage equal to your Ice damage to your target and enemies within 5 feet from it.

Siphon Life

At 18th level, you gain the ability to reap life energy from creatures you kill.
Once per turn when you kill one or more creatures, you regain hit points equal to highest monster challenge rating killed this turn. You don’t gain this benefit for killing constructs or undead.