Diamond of Everwinter

Wondrous item, legendary (requires attunement)

This icy blue-white diamond is cold to the touch and mounted on a mithral chain. Crafted by an ancient cabal of winter witches and frost wizards, this necklace provides you with the following benefits while you wear it:

• You are protected from extreme cold, able to tolerate temperatures up to -100 degrees Fahrenheit without further gear, and you are cooled in extreme heat, suffering no ill effects from temperatures up to 120 degrees Fahrenheit.
• You do not require food or water.
• You ignore difficult terrain created by ice or snow.
• You have resistance to cold and fire damage. If you would be damaged by cold or fire, you may divert the remaining damage to the diamond.

The diamond has 70 hit points and it must absorb all remaining damage you did not. If this exceeds the diamond’s hit points it absorbs all damage from the effect but is destroyed. As long as the diamond of winter has at least 1 hit point remaining, it continues functioning and regains 1 hit point after each dawn. Spells such as mending or make whole have no effect on the diamond.

Epic Attunement. If you have at least one epic boon or blessing (see Chapter 6 of the 5E Game Master’s Guide) or legendary action ability, the diamond of everwinter provides you with the following additional benefits:

• The diamond of everwinter now regains a number of hit points each dawn equal to your proficiency bonus.
• You can render up to 9 allies impervious to cold temperatures up to -100 degrees Fahrenheit.
• You may either spend a legendary action or inflict a number of hit points equal to your proficiency upon the diamond to cast a spell with its damage type turned to cold.
• You may use a legendary action or inflict a number of hit points of damage equal to your proficiency bonus onto the diamond of everwinter to transport yourself and others through arctic terrain. This effect functions like transport via plants, but your current location and destination must each be adjacent to a Colossal mass of solid ice filling at least a 30-foot cube. The ancient covens that created the diamonds of everwinter had a series of hidden retreats, and it is believed that speaking the name of such a place when activating this ability will transport you and your companions to that location.

As you increase in power, so, too, does the power the diamond of everwinter grants to you: Each time you gain a new epic boon or legendary action while attuned to the diamond of everwinter, you gain one of the following spells as an ability you may use once per long rest (if you have legendary actions, you may expend one for an additional use of this ability as well): animate objects, create food and water, fabricate, hallucinatory terrain (DC 17), meld into stone, move earth, stone shape, water walk. The effects of these abilities only affect objects and terrain features of ice and snow, in place of objects and terrain they normally affect. You may only select an ability if its spell level is equal to or lower than your proficiency bonus.