Auril's Cold Heart

 This small, blue glowing stone pulses slowly with power. When attuned, it buries itself in the wielder's chest. Once attuned, it cannot be removed without divine intervention or the wish spell.

Dormant

While wielding Auril's Cold Heart in its dormant state, you gain the following benefits:

• You have advantage on Wisdom (Perception) checks that rely on sight, you are immune to cold, and you have darkvision out to a range of 60 feet. If you already have darkvision, this increases the range of your darkvision by 60 feet. Your eyes turn frost blue.
• As an action, you can use the cold heart to cast polymorph on yourself, transforming into a Dire Wolf or owl while retaining your Intelligence, Wisdom, and Charisma scores, as well as the properties of the heart. This property can’t be used again until the next dawn.
• With ten minutes of preparation, the attuned bearer can enter a sub-plane that is controlled by Auril. This works as per the Rope Trick with the following changes; only the person attuned to the shard can enter this space. It is incredibly cold. Auril's presence can be felt at all times. The spell lasts 8 hours.
• At any time while they still draw breath, the bearer may opt to become Reborn, as per the lineage. They can only do this once. If unconscious at the time, they immediately gain half their maximum hit-points and the Deathless Nature feature.  They detect as undead.
  
  

  Awakened

  While wielding the heart in its awakened state, you gain the following benefits:

  • You have resistance to psychic damage and immune to cold damage.
  • You can use an action to cast the Inflict Wounds spell at level 5, without any components. This property can’t be used again until the next dawn.
  • When you cast the polymorph spell using the heart you can transform into a Awakened White Moose.

  Exalted

  Bearing the heart in its exalted state, you gain the following benefits:

  • You no longer age.
  • You gain a flying speed equal to your walking speed.
  • Your teeth become razor-sharp natural weapons, which you can use to make unarmed strikes. If you hit with them, you deal piercing damage equal to 1d6 + your Strength modifier, instead of the bludgeoning damage normal for an unarmed strike. You can make this attack as a bonus action. When you bite a creature and deal damage to it, the creature must succeed on a DC 17 Constitution saving throw or be poisoned for 1 minute, as their blood turns to ice. The target can repeat the saving throw at the end of each of its turns, ending the condition on itself on a success.
  • You can cast the Create Undead as a seventh level spell every full moon.

Notes: Immunity: Cold, Advantage: Perception, Sense: Darkvision