Shadows of Hel

As an action, you summon shadows from the depths of Hel and create create a thick cloud of darkness, with a radius of 20 feet, centered on yourself and lasting 10 minutes. The area within the darkness is considered heavily obscured. You and any allied creatures that are in the radius when cast, however, can see through the darkness. The darkness spreads around corners and cannot be dispersed.

You and a number of allied creatures equal to your proficiency bonus gain temporary hit points equal to your warlock level. You can use this once per short rest.