Soul Ring

Wondrous, rare (requires attunement by a Spellcaster) While attuned, as an action, you can roll and expend any number of your unused hit dice, and lose HP equal to the total rolled. You regain one expended spell slot level equal to the hit dice expended, up to 5th level. A ring that feeds on the souls of those who wear it. Created by u/KelsierHathsin

This magical ring has 5 charges. While attuned to it, you can use an action to expend 1 or more of its charges. You lose 10 life and regain one expended spell slot level equal to the charges expended, up to 5th level. The ring regains 1d4 + 1 expended charges daily at dawn. If you expend the ring's last charge, roll a d20. On a 1, the ring crumbles into ashes and is destroyed.