Destiny 2 players on the Essence of Vanity quest are going to need an item called the Horned Wreath to complete the quest and earn the Tranquility sniper rifle. Players will need to traverse deep into the Moon, back to a location that will be well known for those who played Destiny 1 that returns in Shadowkeep's new Moon destination.
From the starting point at Eris Morn, Destiny 2 players need to traverse through Anchor of Light to the Hellmouth and head to the right side of the area from that entrance into the area. This is the path that players took for the Summoning Pits strike in Destiny 1. Players can either fight their way through or speed run past the enemies. The final destination is the Chamber of Night, which again will be a familiar location for veteran Destiny 1 players who played through the content of The Taken King expansion.
The Chamber of Night was part of the first game's mission where players started their speedrun back to Taniks' ship for the hidden Black Spindle mission. The Horned Wreath is pretty much as far back into the area as players can go, but a waypoint should appear as players enter the Chamber of Night. YouTuber NinjaPups has a great video that shows the entire route:
After players find the Chamber of Night and collect the Horned Wreath, the rest of the Essence of Vanity quest requires players to complete patrols, public events, and Lost Sectors on the Moon and get sniper rifle kills. Once all that is done, players will be able to craft Tranquility, the Legendary sniper rifle from the new Moon gear set.
Tranquility is a kinetic Adaptive Frame 90 RPM sniper rifle, the same archetype as the Beloved sniper rifle (a popular sniper from the Menagerie) but with a bit lower stats overall than Beloved. It can roll with a number of perks, including No Distractions, Firing Line, Snapshot Sights, Fourth Time's the Charm, and Box Breathing. The curated roll in the database includes the Dragonfly perk, but it is currently unknown how players can earn the curated roll.
Destiny 2: Shadowkeep is available now for PC, PS4, and Xbox One, with a Stadia version also in development.