Chamber of Night

The Chamber of Night is a deep chamber of the Hellmouth on the Moon, reached from the Sanctuary or Anchor of Light by heading past the lunar station to the Temple of Crota. From there the route runs through the World's Grave and Circle of Bones, with the Hall of Wisdom on the way. Keep right at forks, pass the fallen columns, and follow the linear hallway to a large chamber, the arena where the Nightmare of Crota appears in a Nightmare Hunt.

The Horned Wreath for the Essence of Vanity quest sits in a small U-shaped cave off to the left at the far end of the chamber, on a rock. Your HUD marks it once you are close. Guides differ on the exact approach, and the routes date from the Shadowkeep era (2019), so the layout may have changed since.