Heart of Ice

Your pact has deepened and your patron has decided to grant you power beyond anything you were ever capable of at the cost of an ever growing icy heart.

You are extremely resilient to cold climates and damage. You gain cold resistance.

(5th-level and higher properties require attunement) As your level increases, you gain the following benefits.

5th level. You have been given the ability to read any language. You now have access to the Eldritch Adept: Eyes of the Rune Keeper feat. In addition, any spell you cast that deals damage, you can choose to deal cold damage instead (no action required).

9th level. You can use your action to create a simple object or structure made of ice, such as a sword, or a solid block. It must reside within a 5 foot cube centered on a point within 15 feet of you. If you attempt to encase the lower half of a creature of Medium size or smaller in ice, the creature can make a Dexterity saving throw. On a success, it evades the effect and is not trapped. If it fails, it is encased in the ice, and is considered restrained. The target remains restrained until the ice is destroyed . If the creature is of Large size or bigger, it automatically succeeds on the saving throw. Ice created in this way has an AC 10 and 15 HP. You may use this ability an amount daily equal to your proficiency bonus.

You can dismiss any of your creations by use of a bonus action.

13th level. you may cast Otiluke's Freezing Sphere once per long rest. Additionally, spells you cast ignore resistance to cold damage, and whenever you deal cold damage to a creature with a spell of 1st level or greater, you can reduce its speed by half on its next turn.

17th level. As an action, you can exude a freezing aura to a distance of 20 feet. For 1 minute or until you lose your concentration (as if you were concentrating on a spell), you have immunity to cold damage, and resistance to fire damage, surfaces within the aura become coated in frost, water freezes instantly, and you take on the appearance of a menacing archdevil of winter.

A hostile creature that starts its turn within the aura must succeed on a Constitution saving throw or take 2d8 cold damage and become restrained until the start of its next turn. A creature that has failed the saving throw must continue making saving throws at the start of it's turns if it remains within the aura. A creature that succeeds on this saving throw is immune to this effect for the next 24 hours. At the beginning of your turn, you can expand or reduce the range of the aura by 10 feet, to a maximum of 100 feet.

You can use this ability once per dawn