Cryomancer's Lexicon (Patreon)

Wondrous item, very rare (requires attunement by a wizard)

This thick book is bound with white leather and is freezing cold to the touch. This book can be used as a spellbook and contains the following spells, which are wizard spells for you while you're attuned to the book: cone of cold, freezing sphere, ice storm, protection from energy (cold damage only), sleet storm, and wall of ice.

The book also has 7 charges. It regains 1d6 + 1 expended charges daily at dawn. While the book is on your person, you can expend 1 or more of its charges for use with the following properties:

Cold Casting. You can expend 1 or more charges from the book in place of using spell slots when casting one of the book's icy spells. For each charge you spend as part of casting a spell in this way, the spell slot level you need to cast it is reduced by 1. You can use an action to cast one of the book's spells, even if you didn't prepare it, provided you use only charges to cast it in this way.

Freeze Over. When a creature that you can see (including yourself) takes damage, you can use your reaction to expend 1 of the book's charges to change the damage's type to cold.

Icy Armor. You can use an action to expend up to 3 of the book's charges to coat yourself in a magical frozen barrier. You gain 10 temporary hit points for each expended charge, and when a creature hits you with a melee attack while you have these hit points, that creature takes 10 cold damage for each spent charge.

Do you remember the first time the frost touched your skin? The last time you felt its burn? Have you ever felt its loving warmth, once you've let it in?

The cold is your home now, and the frigid tempest your welcoming parent.

Now: go and welcome others to the family.