GH 24: Fiend 4 — Gift of Unbridled Power

This is a Gift of Damnation you can receive from the Devilish Contractor Boon.

Upon finishing a Short Rest, you can spend 2 Hit Point Dice and regain a number of spell slot levels equal to the highest number rolled. However, you take Psychic damage equal to twice the total that you rolled. You regain the reuse of this gift when you finish a Long Rest.