Destiny 2 Duality Dungeon Guide – How To Beat Every Encounter And Find All Collectibles

Duality brings a new set of mechanics to Destiny 2, taking players into the mind of Calus deep within the Leviathan. The exiled emperor has a whole lot of psychological baggage, and in order to understand what he’s trying to accomplish in Season of the Haunted, you and your fireteam are going to need to execute a “mind heist” and unlock his inner secrets.

The dungeon is not only tough, with three boss fight encounters along the way that drop rewards, but it’s also riddled with secrets. Contained within Duality are 12 Repressed Memories for you to find, which provide additional context about Calus. Finding them all also rewards you with a better shot at getting Heartshadow, Duality’s Exotic sword. Here’s everything you need to know to complete the dungeon and unlock all Calus’s secrets within.

Weapon and subclass recommendations

Duality will push your enemy clearing abilities–like Lost Sectors on the moon and other activities that include Nightmare enemies, it includes a lot of tough fights in which the boss you’re trying to destroy is immune, and a flood of other Cabal troops will be the real risk you’re facing. Thus, you’re going to want to be able to kill lots of enemies quickly and to weather assaults from lots of directions at once, while turning on big damage at key moments in boss fights.

There are a lot of weapons that will serve you well here, but given the release of Solar 3.0 this season (and Void 3.0 last season), it’s advisable that you try to synergize with your subclass and take advantage of new elements that can power up your weapons. For instance, a Calus Mini-tool with Incandescent can be extremely useful for Titans for generating Sunspots, as killing an enemy with the gun can cause them to explode, spreading Scorch to other nearby enemies. Any enemy you kill with Scorch drops a Sunspot. On the Void side, Volatile rounds can be extremely useful throughout the dungeon, so they’re worth considering too.

In addition to a good add-clear weapon like a submachine gun, which will be your main workhorse, consider guns like Witherhoard (which can also clear enemies quickly and efficiently) as well as grenade launchers with blinding grenades, or slug shotguns. Weapons that can activate the dungeon’s main mechanic, the bell of conquest, in a single shot are very helpful, as are any that can drop Cabal Incendiors quickly–you’ll be shooting a lot of them. If you’ve got a decent primary or special weapon you can rely on for boss damage, carrying an accurate machine gun can be excellent for quickly clearing annoying Bell Keepers and other enemies throughout Duality.

And of course, you’re going to need to lay down a lot of damage on bosses as quickly as you can, especially because Duality has several major fights where your windows to do damage to boss enemies are pretty short. There are various strategies to this end: Slug shotguns with Auto-loading Holster can do well, as can linear fusion rifles or rocket launchers like Gjallarhorn (although that last one is very risky with all the enemies running around). Some strategies involve blasting bosses with the Tractor Cannon Exotic shotgun to gain bonus damage for other weapons, like grenade launchers and shotguns. Swords can also be very useful since all boss fights will be fairly active and close-range, and a team rocking The Lament can dish out quite a bit of damage quickly. Generally, in our team and solo runs, we’ve relied on linear fusion rifles like Sleeper Simulant and Stormchaser, but go with the options that feel good for your group and sync up with your best gear.

As you’re building your loadout, also note that there are no Champions in the Legendary version of Duality, so you won’t need any of the corresponding mods.

Entering Duality

The entrance to the Duality dungeon is beneath this statue–the dungeon is actually inside the mind of Calus.

Dropping down beneath the Calus statue, you’ll immediately be confronted by the dungeon’s main mechanic. There are actually two versions of every room within the dungeon: the “dream” version and the “nightmare” version. You’ll know the nightmare version from its red hue–during boss encounters, note that you can only be in the nightmare version of the room for a set amount of time, and if you stay too long, you’ll die from a debuff called “Nightmare Collapsing,” so watch that timer.

Swapping between the two rooms allows you to progress through the dungeon, and if you’re ever stuck, you probably need to swap rooms in order to move forward. In this first hallway, you can see the problem–you’re trapped behind a grate and can’t move on. Look through the grate, across the room ahead, and you’ll see a red bell of conquest with swirling nightmare energy around it. Shoot that bell and you’ll be transported into the nightmare version of this room, where the way forward is no longer blocked.

The main mechanic of the dungeon is using these bells of conquest to travel between the dream and the Nightmare. In the Nightmare version, seen here, you need to stand within the wrong around the bell to transfer or you’ll be killed.

Duality includes a lot of jumping as you navigate through dream and nightmare versions of the same room. In the dream room, you can shoot the bell from anywhere, but that’s not the case in the nightmare room. If you get close to the bell in the nightmare version of the room, you’ll notice a ring around it on the floor. You need to be standing within this ring when you shoot the bell to transfer yourself back to the dream world from the nightmare world; if you’re too far away from the bell, you’ll die. You’ll need to keep this in mind for the rest of the dungeon and remember to get right next to the bell in nightmare rooms before you shoot them.

After crossing to the bell and shooting it, you’ll find yourself back in a new dream version of the room, only this time, it’ll be populated by enemies. Clear them out and start climbing the ledges and beams around the room. Your goal is to get to the top, but along the way, you’ll find your first two Repressed Memory pickups, which provide additional lore for the dungeon and help you earn the Mind Heist Triumph. Earning that Triumph increases your chances of earning the Heartshadow Exotic sword upon completion of the dungeon, so it’s definitely worth doing.

Repressed Memory 1: The first dream room

Look for an open door on the right wall to find the first Repressed Memory, hidden in the shadows.

After clearing the first enemies you come across, you’ll start to climb the walls of the room to reach a higher location and the path forward. Facing up the stairs near where you first start, the Repressed Memory you’re looking for is on the right side, high above you. Climb up on that side using the beams in the center of the room and the ledges at its back. Once you get high enough, look for a series of ledges and alcoves lining the wall. The alcove near the center of the room, toward the back, will contain a slightly opened door instead of a blank wall. Through it, you’ll find the first memory.

The memory is through the door, deeper in the room.

Once you’ve got your first memory, climb as high as you can and look to the wall across from you to find another grate, through which you can shoot another bell. That’ll transfer you into the nightmare version of this room, where you can continue forward, but not until you grab a second memory.

Repressed Memory 2: The first nightmare room

The same place you found the first Repressed Memory also holds the second, but you’ll need to travel to the Nightmare to find it.

The second memory is actually in the exact same location as the first one–but in the nightmare realm, rather than the dream realm. Once you’ve shot the bell, you should be able to turn back toward the right wall and see the ledge you need. As before, it has an open door in the wall; jump down to it and go inside to find the second memory at the end of a long hallway. You’ll then need to jump back down to the floor below and shoot the first bell you used to return to the dream realm and climb back up to where you were.

Back at the top of the room, shooting the bell will transfer you to the nightmare, where you can advance forward. You’ll need to make a jump from the beams to an opening across the room, where you’ll reach the next bell.

In the next room, you’ll see some enemies hanging around on ledges and beams. The bell you want to shoot is on your left, through the grated wall. Back in the nightmare realm, look for the way forward along the left wall, which will lead you into the underbelly of the Leviathan and to your next bell. After activating the bell, drop down as far as you can and look through one of the grates in the wall to spot a bell across the room just beyond.

Repressed Memory 3: Near a bottomless pit

Look down around the back of this column to find the next Repressed Memory.

As soon as you shoot the distant bell here, you’ll find a hole in the wall that will let you exit this hallway into a big, open room. As you step through the opening, turn left and look down. You should see a vertical column with a small platform jutting out of it. Jump down to this platform and spin 180 degrees back toward the way you just came. You should see another column opposite you across the room, with its own platform, and a Repressed Memory sitting on it.

After grabbing the memory, leap back around to the ledges hugging the walls. You’ll have to fight through a handful of enemies once again. The exit is ahead on the left side of the room, taking you back into the Leviathan’s underbelly. Ahead, you’ll find another bell to transfer yourself back, but watch out for an elite Cabal Gladiator hiding around the corner as you pass.

Back in the dream realm, drop down once again (watch out for another Gladiator at the bell when you come through). Continue until you reach a room that looks like a nice lounge for Calus, with a big square section in the center that has some curtains hanging off it. This room will be filled with enemies, and you’ll need to kill them all in order to reveal the path in the center of the room that lets you drop down. Before you go, however, you’ll want to grab another Repressed Memory.

Repressed Memory 4: Atop the opulent room

The exit to this room is a metal door that opens in the floor once you kill all the enemies. Before you go, climb up in the back of the room to find the Repressed Memory.

In the room with the columns and curtains, jump up on top of one of the light fixtures in order to climb up to the top of the room. You want to get above the section of columns along one of the walls. You’ll find the Repressed Memory in the center of this area.

Drop down through the hole in the center of the room to reach your first boss encounter, which will require you to use the bell mechanic to destroy one of Calus’s Nightmares.

Encounter 1: Nightmare of Gahlran boss fight

The Gahlran fight will help you learn how to deal with the rest of the dungeon’s fights–once you understand how this fight works, you’ll know everything you need for the others. The room you’re in is fairly long, with a big open area in the center and a bell at either end. Along the side walls are four doors, with two near the bell at one end of the room and two near the other, elevated bell. If you take a look at these spots, you’ll see that there are emblems on the ground and on the tapestries nearby, and those emblems will also appear as holograms emanating from the ground.

Find the corresponding Standard Essence in the Nightmare version of this room in order to open these doors.

You’ll find in a second that the boss in this fight is immune for most of the battle, so your goal with these emblems is to pick up items and place them in their corresponding locations on the ground in order to make Gahlran vulnerable to damage. You’ll need to jump back and forth between the dream world and the nightmare world to get the things you need in order to make him vulnerable, so try to memorize the layout of the room. If you’re facing the elevated bell, the Chalice emblem is on the left near the elevated bell and the Axes emblem is on that same side near the lower bell; the Sun emblem is on the right near the elevated bell and the War Beast emblem (or Dog emblem) is on that same side near the lower bell.

Start the encounter by shooting one of the bells, making a note of which one you use, which will transfer you to the nightmare realm. Here, you’ll face a bunch of Cabal Legionary enemies. They back up a big, immune Gahlran who will chase you around the room, so you’ll need to avoid him. Near each of the bells, you’ll have distant Psions sniping at you, so try to stay out of their line of fire. Note when you arrive that the Nightmare Collapsing timer appears on your screen, counting down from about a minute. When that timer hits zero, you’ll die, so you need to make sure to leave the nightmare realm before the timer runs out.

Unlike the bells you’ve dealt with before, during this boss fight, bells are locked off when you use them by Incendior enemies called Bell Keepers. If you used the elevated bell to enter the nightmare, for instance, then two Bell Keepers will spawn in the nightmare, and you can’t use the bell to leave the nightmare until those Bell Keepers are dead. What’s more, in the nightmare, Bell Keepers appear at the opposite end of the room from the bell you used. So if you used the elevated bell, you’ll need to run to the other end of the room to kill the Bell Keepers, and then return to the bell in order to use it to escape the nightmare. Since the Nightmare Collapsing timer can kill you, that means prioritizing Bell Keepers and eliminating them quickly is always extremely important.

Standard Bearers are waiting in two of the four side rooms in the Nightmare version of this arena. Find them and pick up the Standard Essences they drop.

When you transfer into the Nightmare realm, you’ll find that the four doors marked by the emblems, which were closed in the dream world, are now open. Two of those four rooms will contain enemies: a group of War Beasts, which are protecting a Psion called a Standard Bearer. When you kill one of these Psions, an item will appear in the center of the room near the door called a Standard Essence that corresponds to one of the emblems. So your goal with your transfer to the Nightmare is to get at least one of these items and bring it back to the dream realm. Ideally, you should split your fireteam up so that two members of your team identify these Psions, kill them, and get their Standard Essences. You can generally tell where the Psions are by checking your radar; when you get near one of the bells, use your radar to identify if there are enemies to your left and right to tell if you should run into one of those rooms. The third member of your team can focus on killing Bell Keepers and preparing for everyone to return to the dream realm. Also, while you don’t have a lot of time in the nightmare realm to find and get your Standards, know that killing a Standard Bearer Psion will add time to your Nightmare Collapsing timer.

Once you have your Standards, bring everyone to the bell and use it to transfer back to the dream–remember that anyone not standing beside the bell when you shoot it will be killed, and if they die holding a Standard, you’ll have to return to the nightmare to get it again. Back in the dream world, holograms will appear near the side rooms, which are closed again, identifying where your Standard Essences need to go. Match the Standard you’re carrying with its emblem and use the action button to place the Standard next to its correct door. When you place a Standard, the door corresponding to it will open, releasing a group of War Beasts and a Colossus to fight you.

As with the last room, it’s a good idea here to give your team specific jobs. The players who have Standards should place them at their doors, while the third player kills Bell Keepers. In the dream realm, a bell can be activated by killing the Bell Keepers on the same side of the room as the bell–not the opposite Bell Keepers like in the Nightmare realm. With the two side doors open, the players who placed their Standards should go into the newly opened rooms. Once they’re inside, the third player should again shoot one of the bells to transfer everyone to the Nightmare realm.

You need to eliminate all the Visions of Gahlran in order to make the boss vulnerable to damage.

The two players in the side rooms will find themselves locked in and will have a fight on their hands. Inside those rooms are a number of Visions of Gahlran, which are weaker versions of the boss. There should be five Gahlrans in each of these rooms, and you need to kill them all. Each one will drop an Unstable Essence, those orange orbs, which give you a brief buff against Nightmare enemies. Note that these versions of the side rooms are locked but they’re linked together, so if you enter through a door near the elevated bell, you’ll need to progress through the room to the door near the lower bell in order to exit. The door won’t open until you’ve killed the Shades of Gahlran, so you want to do so as quickly as possible.

Meanwhile, again, the third player should kill the Bell Keepers in order to clear the path out of the nightmare realm. When all the Shades of Gahlran have been killed, the Nightmare of Gahlran boss in the center of the main room will become vulnerable. If you’re quick about it, you’ll probably have around 40 seconds to do damage to the boss before you have to leave. Damage Supers are good here, as is something like Well of Radiance, which will protect you (and give your teammates the Radiant buff) while you do damage. Gahlran will continue to attack you while you damage him, as will all his Legionaries, so be sure to protect yourself.

Keep an eye on the Nightmare Collapsing timer–when it gets around 15 or 10 seconds, disengage with Gahlran and make your way to the bell and escape the nightmare realm. Gahlran will stop being vulnerable at that point, so you’ll have to repeat the process of gathering emblems in order to damage him again. If you’ve got the rhythm down, however, you should be fine–there’s nothing else you need to know or do, and a team that knows the layout of the room well and is good at their roles should be able to kill Gahlran in two or three phases, or even just one with solid damage.

Defeating Gahlran rewards you with a chest and opens the way deeper into Calus’s mind through a door in the floor. Don’t leave just yet, however–there’s a Repressed Memory to find.

Repressed Memory 5: In the War Beast room

Before leaving the Gahlran fight, check the War Beast room to find a Repressed Memory.

Before dropping down the newly opened hole in Calus’s boss room, head to the door marked with the emblem of the War Beast–it’ll be near the lower bell. Head toward the back of the room on the right side to find a Repressed Memory waiting and easy to grab.

Drop into the hole when you’re ready to move on. The next portion of the dungeon might be considered its “jumping puzzle.” Follow the pipes until you reach a big open room, where Calus will discuss someone he lost. This is a crypt, and you’ll need to make a pathway of platforms in order to advance.

The crypts area requires you to hit several switches to release the crypts and use them as platforms.

As you enter the crypt room, look down and left to find the path forward and a few enemies to clear. Drop down, watching out for an Incendior that’ll come through the door behind you when you land. As you advance, you’ll find a switch to flip, which will cause several of the triangle-shaped tombs set in the wall ahead of you to extend outward, allowing you to climb them. The path forward goes to the right, but you’ll need to backtrack here in a moment.

From the switch, use the tombs to climb up to a flat platform. Cross the room back to the other side and keep climbing up, where you’ll find a few more enemies and another switch. This second switch opens the exit, which is directly across from you–watch out for an Incendior and some snipers while you’re here. Before heading to where the snipers spawned, however, you’ll want to head back toward the first switch for a Repressed Memory.

Repressed Memory 6: The high crypts

Once you’ve activated the second switch, return to the wall and turn left to climb a new set of crypts.

Return to the far side of the room and turn left. The second switch should have pushed out two new crypts that allow you to climb upward, but moving back toward the first switch in this room. At the top, you’ll have to jump around a column jutting out from the wall to reach another platform on the other side, and a Repressed Memory.

At the end, you’ll find a column blocking the path forward; jump around it to find the Repressed Memory.

Spin back around and hug this left wall to continue toward the exit. Use the tombs to jump to a second doorway through which a pair of psions and a phalanx enter the room to attack you. Clear them, then climb up the last two tombs ahead of you to find a tunnel in the wall on the left that’ll let you finally leave this room.

The tunnel leads to a drop you’ll need to slide down, which will put you back in the Leviathan’s underbelly. Be careful here, as the fall can kill you, so use some jumps along the way to slow yourself down. At the bottom, hang a left and follow the passageway to its end; you’ll fight a few Cabal enemies along the way, including tough Executioners and a Colossus. Eventually, you’ll come to a brightly lit gap you’ll have to jump over, but don’t leap into the light just yet.

Repressed Memory 7: At the brightly lit chasm

This jump hides a Repressed Memory, which is immediately beneath this platform.

When you get to a small platform over a gap, where you’ll need to leap to a catwalk ahead, stop and look down over the edge. You should see a spot below where you can drop down, and then another directly beneath the platform you’re on. Drop to this second location and check beneath where you started to find your Repressed Memory.

You can see the place where you can reach the memory from the catwalk on the other side of the gap.

When you’re ready, leap across the chasm to the catwalk, then follow it to the right to enter another vent tunnel. At the end, you’ll drop into a big room with several large Cabal Bather statues. Don’t move just yet, however, as there are a few things to nab here.

Hidden Chest 1: The statue vault

The platform to the left of the entrance includes a slightly open door, with the hidden chest located just behind it.

Before jumping down from the high platform from where you start, you should see platforms identical to the one you’re on straight across from you, on your right, and on your left. Each has a closed door at the back, except for the platform on your left; the door there is slightly cracked open. Leap up to it from the center bell platform and go through the door to find a hidden chest, which will dish out any items you’ve already earned from within the dungeon.

Repressed Memory 8: The statue vault Nightmare

Look behind the column in the Nightmare room that’s straight across from where you enter the statue room to find the Repressed Memory.

Shoot the bell in the center of the room in order to flip to the Nightmare version of this area. Around the room, you’ll see several platforms, with four larger platforms behind each of the statues. Leap up to the big platform opposite where you came in and check behind the column at its back to find the Repressed Memory.

The path out of this room is actually in the floor; there’s a big bank vault-like door in the center of the room beneath the bell, and you’ll need to align the statues in this room in order to open it. There are four statues, and you need to rotate each one so that its axe is pointed at the center of the room. The trouble is, the switch for rotating the statues is in the Nightmare version of the room, which doesn’t show you where each statue is facing, so you need to remember how each is aligned when you enter in order to know how many times to turn each one.

This isn’t too tough a puzzle, however. In the Nightmare room, you’ll find a switch that looks like Calus’s face at the base of each statue, at the back. Each time you use the switch, it’ll rotate that statue a quarter-turn counterclockwise. There are four statues, starting with one immediately below where you enter the room.

Entrance statue: three turnsStatue to the left of entrance statue: two turnsStatue across from entrance statue: two turnsStatue right of entrance statue: no turns

You should hear a big clang sound if you’re successful, but even if you’re not, just use the bell to travel back to the dream version of the room and figure out what you need to change about the statues. When they’re all properly aligned in the dream, the vault door will open and you can drop down to the dungeon’s next encounter.

Encounter 2: The Vault

You’re working to open this vault door in the floor, with bells of conquest on either side of the room. This vault door disappears in the Nightmare room, so be careful not to fall through the hole it leaves behind.

Your second big fight of Duality is more about managing waves of enemies than it is about dealing with a specific boss. Still, the mechanics are pretty similar to the fight with Gahlran, requiring you to travel back and forth between the Nightmare and dream worlds, and to gather Standard Essences along the way.

When you first trigger the fight, you’ll find that the room is divided into four parts. The center section of the room is a round platform, and in each of the corners, enemies will flood in, dropping down beside large walls toward the back of each section. Either end of the room has a bell, and beneath those bells, you’ll find the Bell Keeper Incendiors that activate them. In the dream version of the room, killing the Incendiors immediately beneath a bell will activate it; in the Nightmare world, the Bell Keepers to activate a bell are on the opposite side of the room.

To complete the encounter, you have to kill three Elite-level Nightmare enemies, one at a time: a Legionary, an Incendior, and a Centurion. Each of those Elite enemies has a shield that renders them immune to attacks, however, so for each wave, you first need to break the shield. To do that, you need to gather two Standard Essences from the Nightmare version of the room; you can see holograms of which two you need projected from a ring around the center of the room. You’ll gather six Standard Essences in total, two for each Elite enemy.

Look for the symbols on these walls in the corners of the dream version of the vault room, which tell you where to go in the Nightmare version.

If you head to each of the corners of the room, you’ll find that the back side of the half-walls located in each one is marked with one of the four Standard symbols. The Chalice and Sun are near the bell that’s up the stairs; the War Beast and Axes are near the lower bell. With each round, you want to identify which Standard Essences you need, and then position yourself at that corner before activating one of the bells. Be careful not to stand in the center of the room when you hit the bell–in the Nightmare version of the room, the round vault door here is gone, leaving nothing but a huge round pit.

In the Nightmare version of the room, each of the corners that’s marked with a Standard symbol leads to another section of the room, which is filled with Legionaries and Phalanxes. Run up the stairs into these areas and then clean them out as quickly as you can, being careful not to get too close to the Phalanxes, who love to smack you with their shields for a quick kill. Once all the enemies are dead, you can run to the end of the room and kill the Colossus waiting there. With that enemy dead, a Standard Bearer Centurion will spawn. Quickly kill it and a Standard Essence will appear on the platform for you to pick up, just like in the last encounter. As in other boss fights in the dungeon, if you kill the wrong Standard Bearer, your timer Nightmare Collapsing timer will be drastically reduced, so be sure to make sure you’re in the room with the right symbol. There are hints in each one as to which symbol marks the room: the War Beast room has a dog statue in the center; the Chalice room has big chalices in the center; the Axes room has axes hanging from the columns on the sides of the room; and the Sun room has a big sun hanging in the back over the Colossus.

Double-check you’re about to kill the right Standard Bearer by checking out the decorations in the Nightmare room. You can see this is the War Beast room from the statue in the center.

With the Essence in-hand, you can return to the dream version of the room. To do so, you’ll need to kill Bell Keepers on the opposite side of the room from the bell you used to get here; you’ll find them on the lower portions of the room, beneath the central platform. The best strategy here for a fireteam is to put two players on Standard duty, while the third kills the Bell Keepers and secures the way back to the dream room. Remember that there’s a timer that will wipe your team if you spend too much time in the Nightmare; it’s extended when you kill the correct Standard Bearers, and greatly decreased if you kill the wrong ones, so double-check your Standards before you enter the Nightmare.

When you return to the dream room, deposit your Standard Essence where you see the hologram. Dropping off two of them will dispel the shield around the Elite enemy, allowing you to kill it. When you do, the next will appear with a new shield, forcing you to repeat the whole process.

That’s all you really need to know to open the Vault; the enemies you face here are standard and not especially tough to kill. If possible, it’s a good idea to shoot the bell opposite the side of the room from where you expect to collect Standard Essences, since that’ll put the Bell Keepers close to you as soon as you enter the Nightmare.

When you’re done, the round Vault door in the floor will unlock, allowing you to drop down. Don’t do that just yet, as there’s one last thing to collect before you move on.

Repressed Memory 9: The Vault encounter

Before leaving the vault, climb the crypts beside on this wall to reach a Repressed Memory.

Before dropping down, head to the side of the room with the bell at the top of the stairs and look to the left. You’ll see several of the crypts you earlier used as platforms. Do that again here, climbing to the top of this wall to find the Repressed Memory.

You’ll need to get up pretty high to find the memory, but it’s not a tough climb.

When you’re done, drop down through the Vault door into the last platforming section of the dungeon. Continue until you get to a room with a big square platform in the center with a sheet draped over it. You’ve got both a Repressed memory and your second hidden chest here.

Repressed Memory 10: Beneath the floor

Look beneath the big platform with the cloth on it to find a Repressed Memory.

Head into the room with the big platform; you should see that the floor is actually elevated here, and you can get down beneath it. Look for the Repressed Memory in the center of the floor here.

Hidden Chest 2

In the base of the platform, you’ll find the second hidden chest.

The hidden chest is in the same place as the Repressed Memory, but a little less obvious. Look for a hole in the base of the platform with the sheet on it while you’re under the floor. Crouch and push to the back of the hole to find the chest.

As with the previous rooms, you’ll need to swap back and forth between the Nightmare and the dream in order to advance here. Head to the central platform and use the bell to swap the Nightmare; your pathway forward is to the left, and you’ll have to jump to some narrow beams to cross gaps. The doorway to the path you need is on the right.

Swapping back and forth between the Nightmare and the dream will allow you to climb to the top of the room with the big white platform. Make your way to the narrow scaffold beams near the ceiling to get a Repressed Memory before moving on.

Repressed Memory 11: The Platform’s Nightmare

As you travel through the platform room, you’ll eventually reach the rafter high above the room. From here, jump to the doorway where you first entered this room to find a Repressed Memory.

This Repressed Memory isn’t tough to get, but nabbing it requires you to repeat the process you just went through to climb to the top of the white platform room. When you get to the beams at the top of the room, turn and look toward the doorway through which you first entered this room; it should be off to your right. From here, you can leap over to that opening and find the Repressed Memory waiting for you. When you’ve got it, hop down and repeat the process of climbing back to the top of the room so you can reach the exit.

You’ll advance to one last platforming area, where Calus will talk about how he named Caiatl. This room is marked by long, slanted beams across a big chasm. Look for objects you can climb on against the wall on the right side of the room, at the top of each slanted beam, so you can get close enough to jump to the next one. Ahead, you’ll see a doorway at the bottom of one of these beams, which will take you to the last encounter. Before you go, grab your final Repressed Memory.

Repressed Memory 12: Outside the final encounter

The last Repressed Memory is above this doorway; use platforms on the sides of the door to reach the platform above.

This one is tough to spot: It’s right above the doorway through which you need to pass to reach the end of the dungeon. To get to it, look for platforms to the right of the doorway that you can use to climb up to a platform directly above the archway you need to pass through. Once there, head deeper into the alcove here to find the final memory.

With that done, you’re free to pass through the archway and your final test: Calus’s Nightmare of Caiatl.

Encounter 3: Nightmare of Caiatl, Princess-Imperial

Unlike the last two encounters, your third battle of the dungeon changes the mechanics up a bit. As you look around the room, you’ll see three bells. Each bell will have a pair of Bell Keepers minding it. In the dream room, killing one set of Bell Keepers activates a bell; in the Nightmare room, you have to kill both other sets of Bell Keepers in order to make your bell active. Keep that in mind when traveling to the Nightmare: You must kill four Bell Keepers before you can use a bell. That’s going to be important later.

Like the past encounters, your job is again to travel back and forth between the dream and Nightmare rooms to collect Standard Essences from Standard Bearers. Your goal is to get four total Standard Essences and dunk them on their holograms in the dream room. That’ll pull back a chain, which you’ll see locked in four columns next to the holograms. The chain pulls back the ram that rings the giant Bell of Proving in the middle of this room, and using that activates the fight’s damage phase.

These holograms dictate what Standard Essences you need; you’ll then dunk them on these locations to pull the chain beside them to ring the huge bell of conquest.

You’re battling a Nightmare version of Caiatl, and she’ll maraud around the dream version of the room, shooting you and using her stomp attack if you get too close. You can’t damage her during this portion of the fight, and mostly, you just want to stay away from her. The stomp attack can bounce you into walls and create chaos generally, and you’ll have enough of that to deal with.

When you start the fight, clear the Bell Keepers first and keep an eye on the various Psion snipers running around; they spawn from the big platforms in the corners of the room. You’ll want to mark those corners, as they are the locations where you’ll find your Standard Bearers. The platforms are marked with the Standard symbols in the dream room, but not in the Nightmare room, so you’re going to need to memorize and make a note of them. Also note that while the dream room has hard purple goop ringing the central arena, in the Nightmare room, the purple stuff disappears and there’s nothing beneath it. In other words, if you transfer from the dream room to the Nightmare room while standing in the purple stuff, you’ll fall to your death, so make sure you’re on solid ground before shooting one of the bells of conquest.

Symbols are marked above these side platforms, but you’ll need to remember which is which when you travel to the Nightmare.

From the doorway where you entered, the symbols are:

War beast – back leftChalice – back rightSun – front leftAxes – front right

As with previous fights, it’s best to divide your team up with different jobs, with one player dealing with Bell Keepers while the other two take out Standard Bearers. As mentioned, you’ll need to kill four Bell Keepers to open the path back to the dream, so it’s best to deal with them quickly and decisively–a sniper rifle or linear fusion rifle is pretty good for this, and you can notch a one-hit kill with something like Arbalest. These Bell Keeper Incendiors are particularly dangerous because of their ability to send you flying, costing you time or rocketing you off the side of the level, so keep your distance whenever possible.

The Standard Bearers are Psion snipers, and they’re fairly easily killed. As with past encounters, however, if you kill the wrong Standard Bearer, you’ll greatly reduce your time, so don’t try picking off the extra snipers to give yourself extra breathing room. You should also be aware of the Colossi in this room–there’s a Colossus at either end, shooting missiles at you that will slow and blind you. They’re also good at messing up your jumps, so do your best to be careful to avoid getting hit or time your jumps so you’re not hit in the air.

Once you have two Standard Essences, return to the dream room and dunk them on their holograms. Two more holograms will appear, and each time you dunk an Essence, Centurions will spawn in the room alongside the Psion snipers you’ve been dealing with. It’s generally best to clear the Centurions out now; it’s a little slower, but they’ll be hanging around when you come back from the Nightmare, and that can make things a lot more annoying when they start to pile up with Bell Keepers and Psions.

Once you’ve placed all the Standard Essences, the chain will turn red. Shoot it to ring the big bell of conquest and start the damage phase against Caiatl.

After you have all four Standard Essences, the chains in the center of the room will turn red, indicating that you can shoot them. Hitting them with a little damage will cause the bell to ring, transporting you to the Nightmare with Caiatl. Here, she can be hurt, but you’ll need to use the bells scattered around the room to do any real damage.

As soon as you get to the Nightmare, spread out and kill all the Bell Keepers as fast as you can. Each pair will activate their particular bell–slightly different than the usual arrangement of opposite Bell Keepers. As you kill them, watch the front of the room where the bigger Bell of Proving is in the dream room; momentarily, Caiatl will appear there, and she’ll immediately run for one of the bells. Watch her to see where she’s going, and then head for that bell too, making sure its Bell Keepers are dead. If Caiatl makes it to the bell before you, she’ll use it to transport herself back to the dream version of the boss room, and you’ll lose your chance to damage her and have to complete the Standard Essences portion of the fight all over again. To slow her down, you can get close to her to bait her into using her stomp attack. Be careful it doesn’t send you over the edge of the area, however.

Use the bells scattered around the arena to stun Caiatl when she gets close to them. Make sure you’re also standing close when they ring–closer than this–to gain a major damage buff.

What you want to do is get your whole team next to the bell Caiatl is moving toward and wait for her to approach. When she’s within about 10 or 15 feet, shoot the bell to activate it. If she’s close enough, Caiatl will be stunned, while the rest of your team will gain a buff that greatly enhances your damage. You’ll have time to empty about a full magazine of your heavy weapon into Caiatl before she snaps out of her stun. When she does, she’ll immediately head for another bell. Beat her to it and repeat the stun process to keep the damage going. You can hit her a total of three times if you’re quick to the bells; just be aware that you’re likely to take damage the entire time, thanks to Psion snipers standing where the Standard Bearers are normally located.

That’s everything you need to know about the fight; repeat the process to damage Caiatl again until she falls for good. Be aware that after three bells, Caiatl will return you to the dream automatically, and you’ll need to face whatever enemies you left behind, plus a new round of Bell Keepers. It’s the post-damage phase that can get dangerous because of so many enemies running around, so make sure to clear them out quickly, or deal with them before the damage phase so they’re less of a bother when you return.

Heartshadow is a random drop you might get after defeating Caiatl, but completing certain Triumphs in Duality raises your chances of receiving it.

Defeating Caiatl will take you out of the dungeon, and offers a chance at its Exotic reward: Heartshadow, a sword that makes you invisible, does increased damage while you’re invisible, and fires projectiles that weaken opponents. The best way to get it is to earn Triumphs in the Duality dungeon that increase its drop rate–but unfortunately, you’ll have to wait for a blessing from the RNG in order to earn Heartshadow.

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