• Players must defeat Shades of Gahlran to make the boss vulnerable
  • Bells will be locked until Bellkeepers are defeated
  • The Glaive of Dreams is essential for the Unstable Essence buff's duration

Like most other content in “Destiny 2,” the new Duality dungeon can be completed by solo players so long as they know what they’re doing.

The Duality dungeon reintroduces some old raid mechanics from the first year of “Destiny 2,” namely Cabal Standards and realm shifting from the original Leviathan raid. These mechanics will be the focal points of this dungeon, and all major encounters will feature them in one way or another.

Duality’s first boss encounter against the Nightmare of Gahlran will have players constantly shift between the normal and nightmare realms. But the boss will only be vulnerable in the latter after completing the necessary steps. This boss can easily be beaten with the right build.

Nightmare of Gahlran Boss Guide

Gahlran is an invulnerable melee enemy who can only be seen in the nightmare realm. To remove his invulnerability, players must kill Shades of Gahlran in two separate rooms inside the boss arena.

First, go to the nightmare realm by smacking either bell in the main hall. Search the side rooms for Standard Bearers, then take their Standards back to the normal realm.

Gahlran is invulnerable until all of his Shades are defeated in the adjacent rooms - Destiny 2
Gahlran is invulnerable until all of his Shades are defeated in the adjacent rooms Destiny 2

Deposit one of the Standards in their matching pedestals and wait for the big room to open. Dispose of the enemies that spawn, then head back to the nightmare realm from inside the newly-opened room. From here, kill all the Shades, then return to the normal world and repeat the process with the other standard.

Gahlran should be vulnerable after both groups of Shades have been eliminated. Take note that the bells will only become usable after defeating Bellkeeper Incendiors that spawn in each realm.

Recommended Loadouts

The easiest way to solo this boss is with a Titan using Throwing Hammers, Synthoceps and Tractor Cannon. Once Gahlran is vulnerable, stack up Roaring Flames and beat the boss down with hammers that can deal up to 200K damage per throw.

Alternatively, Warlocks with Starfire Protocol and Fusion Grenades or Blade Barrage Tripmine Hunters with The Lament exotic sword can work well if played properly. Use the Classy Restoration and Armor of the Dying Star mods from the seasonal artifact to boost survivability and get as much Resilience as possible.

Lastly, bring a glaive with the Glaive of Dreams mod to maximize the uptime of the Unstable Essence buff.