Duality dungeon guide - Destiny 2

A complete walkthrough of the Duality dungeon in Destiny 2, including tips for the Master difficulty.


The Duality dungeon is the latest three-player endgame content to hit Destiny 2. Released on May 27, 2022 during the Season of the Haunted, the Duality dungeon takes players into the mindscape of emperor Calus to steal his darkest secrets. If you want to clear this activity with minimal fuss, we’ve got a Duality dungeon guide to help you navigate each section, a walkthrough for each boss, and some tips for the Master difficulty.

Duality dungeon guide

The Duality dungeon is located in on the Moon in the Derelict Leviathan. Make sure you know how to start the Duality dungeon and remember to pick up the quest from Hawthorne. The Legend recommended Power is 1550 while the Master sits at 1590.

Master Duality changes

  • All Bellkeepers have Void shields
  • Incendior Unstoppable Champions in normal realm side rooms during Gahlran fight
  • Colossus Barrier Champions in Nightmare realm in the Vault
  • Colossus Barrier Champions in Nightmare realm during Caiatl fight

Arbalest will ensure you can swiftly deal with Barrier Champions in the Nightmare realms. Have a couple of teammates use Void weapons so that Bellkeeper shields will always be broken. Use appropriate Exotic weapons or seasonal mods to handle Unstoppables.

For damage phases, nothing drastic changes between Normal and Master. Expect to take a few more rotations to deal enough damage. Survivability will be key here, so use mods that assist with regeneration and damage resistance:

Duality dungeon weapons and builds

The launch of Season of the Haunted introduced Solar 3.0, which means builds have been shaken up something fierce. Hunters should consider using Blade Barrage as its damage output is one of the highest at the moment. Warlocks will likely want to lean into a Fusion Grenade and Elemental Well build popularized Aztecross. Titans would do well for Ward of Dawn or even Code of the Missile for a whole lot of damage.

destiny 2 duality dungeon weapons and builds

In terms of weapons, Gjallarhorn remains a worthwhile weapon for boss damage and Divinity works well with the Seasonal Artifact Trace Rifle mods. Other than those, use weapons that synergize well with your build – things like Funnelweb, The Title, and Austringer.

Enter the Echo of Calus’ Consciousness

destiny 2 duality enter calus mindscape

Walk to Eris and listen what she has to say. When she tells you to enter, walk towards the statue of Calus and fall down the hole.

Navigate the Mindscape

destiny 2 duality guide shoot bell

When you’re teleported into a small hallway, walk up to the bars and shoot the bell in the distance. This will teleport you into the next room.

From here, the goal is to shoot the Bell of Conquest, which causes you to be teleported between reality and the mindscape. When you are in reality (the non-red version of the Leviathan) all players must be near the bell when it is shot or they will die.

destiny 2 duality dungeon bells of conquest

In the large room, climb up the rafters to the very top to spot another bell high above the first one. Stand on the rafters to be teleported to a safe spot in the mindscape.

destiny 2 duality dungeon

Move into the next large room with the Calus face that has a glowing mouth – the next bell is on the left. When you enter the mindscape version, move forwards to find an access tunnel on the left.

Pass through the access tunnel and shoot the next bell. Back in reality, drop down into the hallway below.

Go out into the large room, defeat the Cabal, and cross the gap to the other side. Find another bell in the side hallway through some pipes.

destiny 2 duality

Walk through the Calus mouth and defeat the enemies. Text will appear on-screen informing you that a Standard Bearer has spawned. A hatch will open in the middle of the room below the chandelier – drop down to reach the next section.

Nightmare of Gahlran, Sorrow Bearer

destiny 2 duality dungeon nightmare of gahlran sorrow-bearer

The first proper boss fight is against Nightmare of Gahlran, Sorrow Bearer. This fight requires players to flip back and forth between reality and the nightmare mindscape, defeat Standard Bearers and collect Standard Essence, and defeat Nightmare Bellkeepers. Whenever you are in the nightmare mindscape, there will be a countdown called Nightmare Collapsing that will wipe your fireteam when it hits zero. Here is a quick look at the steps for the boss fight:

  1. Defeat Bellkeepers to summon Bell of Conquest
  2. Shoot Bell of Conquest to enter nightmare mindscape
  3. Defeat Standard Bearers and acquire Standard Essence
  4. Defeat Bellkeepers and shoot Bell of Conquest while standing near it to return to reality
  5. Deposit Standard Essence, defeat Bellkeeper, enter Colossus side rooms, and shoot Bell of Conquest
  6. Defeat Visions of Gahlran and Bellkeepers
  7. Deal damage to Nightmare of Gahlran, Sorrow Bearer and use Bell of Conquest to leave

Use a raid banner if you need to and then shoot the Bell of Conquest to start the encounter and travel to the mindscape. Immediately split off into the side rooms to find and defeat the Standard Bearers. Two of the four rooms in the corners will contain a Psion Standard Bearer. A Standard Essence will appear at the entrance of the room when the Psion is defeated, grab it and get ready to leave the nightmare.

destiny 2 duality dungeon standard essence

Defeat all Nightmare Bellkeepers to activate the Bell of Conquest, allowing you to travel back to reality and deposit the essence on the correct plate. There is a plate for the Chalice, Sun, Dogs, and Axes.

When you deposit a Standard Essence, side doors will open and Colossus Cabal will spawn. Enter these side rooms, defeat the Cabal. Shoot the Bell of Conquest while standing in these side rooms to be teleported into the closed rooms in the mindscape version. There must be at least one player in each side room.

destiny 2 duality dungeon vision of gahlran

After being teleported into the side rooms in the nightmare, there will be Visions of Gahlran to defeat. Defeat them all as you run down the hallway. When all are defeated, doors will open granting access back to the Nightmare of Gahlran who can now be damaged.

destiny 2 duality dungeon nightmare gahlran damage phase

Quickly defeat the Bellkeepers and damage Gahlran. There is a 60 second countdown that will wipe the fireteam when it hits zero. Use the Bell of Conquest to teleport back to reality before the timer ends.

Repeat these steps as many times as needed until Gahlran is defeated. The only time you have a time limit is when you are in the Nightmare. If you are in reality, you can hang out in the room defeating enemies to get more Heavy Ammo.

Navigate the Crypt

After defeating Nightmare of Gahlran, Sorrow Bearer you can collect your reward from the chest and drop down the hole in the ground.

destiny 2 duality dungeon navigate the crypt
Use the lever to extend tombs in the chasm.

Continue through the room until you reach the chasm. Jump across to the other side to find a lever down low. Activate it to extend a series of tombs along the wall. Climb up the tombs and cross the chasm again to the original side to find another switch and activate it. Cross back again to the lower platform and climb up the next set of tombs. Look for the hole in the side of the wall at the top of the tombs.

Go down the chute, defeat the enemies, head through the door on the left. In the next room, climb up to the higher level and continue through the hallway. You will come to a chasm with a thin platform in the middle, jump to it and crouch through the access tunnel.

destiny 2 duality dungeon find the way
Use the Bell of Conquest to travel to the nightmare version of this room. Activate the buttons on the statues to turn in real statues 90 degrees counterclockwise.

In the room with the four statues the goal is to turn each statue so each one is pointing inwards - the only hint you have is the tooltip "Find the Way". To do this, use the Bell of Conquest to travel to the nightmare mindscape. Each statue in the nightmare will have a button that turns the real statue by 90 degrees. Take note of which statues need to be turned. You can switch back and forth between reality and nightmare until all are facing inwards, at which point the floor in the middle will open.

Open the Vault

The next major encounter requires players to open the vault. The goal here is to defeat three Nightmares, which is done by depositing a total of six Standard Essences. For every two Essences that are deposited, the Nightmare will become vulnerable. Here’s how the encounter will proceed.

destiny 2 duality dungeon open the vault

Start by noting which symbols appear on the ground – these are the symbols you must acquire. Look in the corner of the areas to find the symbols marked on the blocks, this indicates where the Standard Bearers appear in the nightmare mindscape.

destiny 2 duality dungeon open the vault standard bearer essence

Defeat the Bellkeepers to activate the Bell of Conquest. Shoot the bell, travel to the nightmare, and locate the area with the matching symbol. Defeat the Phalanx and Colossus to spawn a Standard Bearer. Once defeated, grab the Standard Essence and head back to the center.

At this point, defeat the Bellkeepers in the nightmare and travel back to reality. Deposit the Standard Essence and clear out the enemies. Repeat the above parts to claim the second Standard Essence. When you deposit this Essence, the Nightmare boss will become vulnerable. There is no time limit here, so take as long as you need to safely do it.

destiny 2 duality dungeon open the vault nightmare fight

Once the Nightmare is defeated, a second one will spawn and you must repeat the entire process. A total of three Nightmares will spawn, when all are defeated, the floor will open up granting you access to your rewards.

If your fireteam is able to, it can be worth collecting the two Standard Essences at once to cut down on the switching back and forth between reality and the nightmare. This isn’t necessary, but it will help speed things up. For damaging the Nightmare, use your Super and Power weapons. The Fusion Grenade with the Touch of Flame Aspect does a decent chunk of damage.

Navigate the Vault

Continue through the vault into the large room with block in the middle covered with cloth. There is a Bell of Conquest in the back left – shoot through the bars to activate it.

Jump out along the platforms and enter the top hole in the wall to reach the bell. Back in reality, climb up the tunnel to reach the top. Look through the bars to spot another bell across the way. Cross the gap in the nightmare to reach another bell. Back in reality, work across the rafter to the opposite side and go down the chute.

destiny 2 duality dungeon dark shrine

The next area is a massive chasm you must work across to reach the Dark Shrine. Go right and work along the wall to reach the red doorway across the gap.

Nightmare of Caiatl, Princess-Imperial

The fight against Nightmare of Caiatl is a straightforward one but difficult to finish given the various mechanics at play and the thin line between damage phase and needing to repeat the whole process. The goal is to retrieve four Standard Essences to ring the large Bell of Conquest and then use the three bells in the nightmare realm to stun Caiatl to enable a damage phase. Here are each of the steps for the fight:

  1. Note which two symbols are needed near the bell chains and locate the balcony with the matching symbol
  2. Defeat all Bellbearers, travel to nightmare, and defeat Psions on symbol-matched balconies
  3. Grab Standard Essence from balcony, defeat Bellkeepers, travel back to reality
  4. Deposit the Standard Essence, defeat enemies, and repeat the steps to get a total of four Standard Essences deposited
  5. Shoot chain once all four Essences are deposited to begin damage phase. Use a small bell to teleport to nightmare
  6. Stun Caiatl by shooting the bell she runs to. Stand beside bell when doing this to get a damage buff. Repeat all steps until Caiatl is defeated.
destiny 2 duality dungeon nightmare of caiatl
Note the symbols above the balconies, this is where the Psions spawn in the mindscape.

Before the fight begins, take note of the balconies along the sides of the wall. There are symbols above each one which informs you of the location of the Standard Essence corresponding to that symbol in the nightmare mindscape. Also note that four chains at the back of the room and the pads on the ground – this is where you deposit the Standard Essences. A projection of the symbol you need is found here, too.

destiny 2 duality caiatl fight

Start the fight by moving into the room. Clear out all the enemies. Defeat all of the Bellbearers to activate the bells. Note the symbols you must collect (near the chains) and position yourself near the correct balcony. When ready, shoot the bell to teleport.

Defeat the correct Psions on the balconies and pick up the Standard Essence that appears. Each Psion you defeat will add time to the debuff. Be mindful of the Colossus foes that spawn at the ends of the arena in the nightmare.

Defeat the Psions on the balconies to spawn a Standard Essence. Only the Psions standing on the balconies with the matching symbol will spawn one.

When you have the Standard Essences, defeat all the Bellbearers and group up on the bell and shoot it to teleport back to reality. Find the symbol near the chain that matches the essence you have and deposit it. Defeat the enemies that spawn and use the bell to go back to the nightmare when ready. Continue this process until you have four Standard Essences deposited.

destiny 2 duality caiatl chains bell of conquest
When four Standard Essences are deposited, the gems on the chain will glow. Shoot a gem to break a chain, causing the large Bell of Conquest to ring. This begins the damage phase.

After the fourth Standard Essence is deposited, the chains will start to glow – specifically the purple gem. Shooting the gem will ring the large bell, teleporting Caiatl and then your fireteam to the nightmare. You can teleport in faster by shooting the chain and then shooting a small bell.

Once inside the nightmare, quickly defeat the Bellkeepers to activate the bells. You must look for Caiatl and spot which bell she runs towards. Quickly intercept her and stand near the bell. Shoot the bell when she gets within a few feet to stun her for 10 seconds. If you are near the bell when this happens, you will receive a damage buff called Waking Resonance.

destiny 2 duality caiatl damage phase dps

After 10 seconds, Caiatl will run to another bell. Quickly run to it before her and do the same thing – shoot it to stun her and gain your buff. Damage her until she moves to the last bell. Go to the last bell, shoot it and then damage her. Once all three bells are used, the damage phase will end. The damage phase will end early if Caiatl makes it to a bell.

All that’s left to do now is repeat the entire process until Nightmare of Caiatl is defeated. If you’re struggling to deal damage, consider having one player on your team use Tractor Cannon to debuff Caiatl. A combination of Gjallarhorn and Legendary Rocket Launchers is also a viable option, as is a Fusion Grenade build for Warlocks during Season of the Haunted.

The Duality dungeon in Destiny 2 is a unique beast and one that will no doubt resonate veteran players. After completing this dungeon, be sure to check out Grasp of Avarice and the Prophecy dungeon for more gear. Once you’ve increased your Power a bit more, return to tackle the Master version for another set of Artifice armor. In the meantime, stop by the Shacknews Destiny 2 Strategy Guide for more help with other endgame content.

Guides Editor

Hailing from the land down under, Sam Chandler brings a bit of the southern hemisphere flair to his work. After bouncing round a few universities, securing a bachelor degree, and entering the video game industry, he's found his new family here at Shacknews as a Guides Editor. There's nothing he loves more than crafting a guide that will help someone. If you need help with a guide, or notice something not quite right, you can message him on X: @SamuelChandler 

From The Chatty
Hello, Meet Lola