From Destinypedia, the Destiny wiki
Last Wish is a Raid in Forsaken, taking place in the Dreaming City. It is the culmination of the expansion's storyline, and is described as being "like the Vault of Glass and Dreadnaught had a baby." It has the most bosses for a raid yet in Destiny 2.  It takes place in an escalating series of encounters throughout the Dreaming City, before culminating within the Keep of Voices, the tower at the head of the Dreaming City. It is the biggest Raid released thus far in the Destiny series, beating out the previous record holder, King's Fall.
Into The Dreaming City
After the Death of Uldren Sov, Petra informs the Guardian that she needs answers (on who drove Prince Uldren to madness) and is heading through the Gateway into the Dreaming City. Petra invites the Guardian and gives them a Shattered Awoken Talisman that will grant the Guardian access to the Dreaming City. Only one problem, the only way to open the gate is Light and Dark energy combined. Petra directs the Guardian to Spider, who tells them that the pieces needed to repair it are in a Lost Sector, stored away. After retrieving the pieces, Spider repairs the Talisman. However, the Darkness needs to be infused into it, so he directs you to the Scorn, who, are infused with Darkness. After infusing the Talisman, the Guardian goes into the Watchtower and goes into the Gateway. After the Guardian arrives in the Dreaming City, they encounter the Taken Techuens and are pulled into the Ascendant Plane, where they are ambushed by Taken, but manage to push through it. As the Guardian pushes through they encounter Rivens Patience and Rivens Warmth. They also encounter Toland, The Shattered who pushes them out of the Ascendant Plane. He says he doesn't want to be their Virgil and foreshadows Savathun's Plan with Riven warning the Guardian about the curse. Toland kicks the Guardian out of the Ascendant Plane. Once out, they rendezvous with Petra at the Oracle Engine so she can find out if Mara is truly alive. They activate the Engine. Mara reveals herself and tells Petra, that the creator of the Dreaming City and former friend of Mara, Riven was Taken, and must be slain before she can escape the City. Henceforth a raid team is assembled for an opportunity of a lifetime...
Kalli, The Corrupted
Guardians will enter a large empty chamber whose layout is similar to that of the Blind Well. Near the center pit, three groups of two icons will appear to give six in total. Heads (two-headed snake), Smile (a snake in a smiley face pattern), Eight (an eight sign), and Infinite (the infinity symbol). One icon will not be shown. There will be a matching plate for each of the icons (I.e. Heads, Eights, and Smiles being shown. Two of each Smile, Head, and Eight plates must be captured. Each plate will have their symbol above or near the side of the plate. Each plate is divided into three sections. Two Taken Blight bombs will be above two of the sections. Stand on top of the empty section of the plate and defend as Taken Thrall attempt to overwhelm the team. If a plate is held long enough, a Major Taken Knight will spawn. Killing the Major Taken Knight is required to "complete" a symbol.
Also be cautious, as Kalli will warp to a random plate and attack with blasts that will knock the player into the air, then "scream" at the player to knock them back. Simply shooting at Kalli will make her teleport away. Shortly after each plate has been captured, damage phase begins, and Kalli will enter the room's center area and attack with bolts and an ability similar to a Psion's Psionic Blast. Sleeper Simulant, Thunderlord, and the IKELOS SG are recommended for damaging her; Whisper of the Worm is not recommended due to her small head. After a short while, she will cast her weapon which will wipe the team. Upon her spell being cast, each Guardian must run into one of the open doors on the side of the well below Kalli, which are tied to the Major Taken Knight enemies. Ensure that you kill a Major Taken Knight to guarantee that a door will be open, or you will be wiped. If your team does not deplete her health, you must restart the damage phase.
You must cleanse all nine plates, including the plates of which symbols do not match with any of the six shown in the center. Doing so will spawn a Taken Ogre per wrong plate (three total).
Shuro Chi, the Corrupted
When you first get to the door of the arena, it will be closed. To open it, the whole team must stand at the door. To the right of the door (before you enter), there is a big rock that you can jump on to get into the arena before the fight starts, allowing you to get a better understanding of what you need to do. Most of this fight is about managing supers, as there are lots of ads. Dawnblade and Orpheus tether are extremely good for this, as tether makes the orbs and Dawnblade get kills - making more orbs. Whisper of the Worm, Sleeper Simulant, and the IKELOS SG are extremely good for boss DPS, and a Well of Radiance will only increase that DPS.
Now that you have your loadout setup, it is time to begin the fight. When you first enter the room, Shuro Chi will be directly in front of you, and will begin a song. You have around four minutes to complete each floor, before the song kills you. Each time you complete a floor, the timer resets. She will teleport a few times to the left, before resting in a specific area. While she does this, tons of ads will spawn. You can not take down her shield until all of them are dead, so they are priority one. Among these ads, there is one yellow health captain called the Eye of Riven. This ad will be seen for most of the raid, and every time it will drop an object upon being killed. You will want to leave this on the ground until Shuro Chi's shield is down, as you will build up stacks of a debuff that, much like greed from Spire of Stars, will kill you after a certain amount of stacks. This debuff will stay for a certain amount of time, so you will need 2 designated players to carry this eye, alternating for each of the 6 phases. After killing all the ads, three crystals will spawn on three plates. While you stand on the plates, you will take damage. You need to have three people pick these crystals up and shoot them at the person hold a crystal to the right (or left, you just all need to shoot in the same direction), making a sort of triangle. This will break her shield allowing you to do damage. You want to do the crystal part fast, as her song's tempo will quicken until you break her shield. Now, if you look down at her health bar, it will have six different bars of health. After breaking her shield, she will begin the obliterate attack that Kalli used. You need to destroy one bar of health to stop her from obliterating you. This is where you pick up the thing that the Eye of Riven dropped. When you pick it up, you will see that you have your Super charged immediately. Using this near Shuro Chi will cancel the obliteration sequence, and she will start it again. You need to use your super right next to her as late as possible, allowing you to give your team as much time as possible to shred the bar of health. After you use your super, the artifact will disappear, and you join your team with DPS. Or you eliminate a sixth of her health before she obliterates you, without using the artifact. After you get down a bar of health, her shield will go back up, and she will teleport to the next area (still on the same floor). Once again, kill ads and break shields. The other person who is supposed to pick up the artifact will use it to cancel the wipe, and she will teleport again. The only difference is that there is a yellow health Taken Ogre that you want to kill.
Now, the next place Shuro Chi teleports to is up a floor. You need to fill 3 sorts of grids. You will see three circles on the walls. Each of these will show part of a symbol, starting with the one on the left. In the middle of this area, you will see nine plates. These plates, like the last ones you stood on to break Shuro Chi's shield, will deal damage. You need to stand on the plates corresponding to the empty parts of the symbol to fill the symbol. There will be 4 people doing this, and the other two will be taking care of the ads in the room, prioritizing the phalanxes. This is because after you stand on the plate, you cannot stand on it again, so if a Phalanx knocks you off, you cannot get back on. After filling all three symbols, you can move upwards, and rinse-and-repeat for another two floors. Keep in mind that the song does not reset until after you fill the symbols, not after the second phase of damage on the floor, and starts immediately after.
Morgeth, the Spirekeeper
Morgeth is the 3rd encounter of the raid that consist of a small, few mechanics to enter damage phase of the boss. The mechanics consist of Taken Strength, Eye of Riven and Umbral Enervation, which will all be explained. In order to start this encounter, someone must pick up the first Taken Strength that floats in front of the slumbered Morgeth.
There will be 10 Taken Strength before the damage phase, 1 to start the encounter, 4 in the 1st wave of spawn, 4 in the 2nd wave and 1 that will spawn where the first one was to enter damage phase. After a player picks up the 1st Taken Strength, taken enemies will spawn. It is recommended that your team is split into 2 teams on the left and on the right. Once the enemies are cleared, the 1st wave of Taken Strength will spawn, 2 on the left and 2 on the right, pick them up as soon as possible. Also, players are restricted to pick up a total of 2 taken strength or else they will die. When someone dies with Taken Strength, the Taken Strength will respawn outside the area.
As you progress within this encounter, Morgeth is slowly charging up its wipe mechanic in increments of 10%, each increment charging exponentially faster. Players must collect taken strength as soon as possible and restrict deaths as much as possible.
Within that 1st wave, there will be 2 Eye of Riven (Taken Captains) and two Major Taken Vandal spawning randomly either on left or right side. Within that wave, Morgeth will activate a debuff call Umbral Enervation. This debuff applies randomly on a player with Taken Strength. Once that debuff is applied to a player, that player will not be able to move and has 20 seconds until death. In order to free that player, someone must kill an Eye of Riven and pick up its weapon and use the Grenade Button to free that trapped player. However there's a cost, the player freeing the trapped person will steal the trapped person's Taken Strength. If the player that's freeing the trapped person gains a total of 3 or more Taken Strength, they will die. It is recommended that a player with 0 Taken Strength frees the trapped person. After the player frees the trapped person and stole his/hers taken strength, that player will not be able to pick up another Eye of Riven weapon for a long period of time.
2nd wave is exactly the same as the 1st wave, 4 Taken Strength, Eye of Riven and another Umbral Enervation debuff. Once successfully completed, the last Taken Strength will spawn in front of it and all players will enter damage phase when someone picks it up. Morgeth's critical spot is any pulsating spot that glows and during the damage phase, Morgeth with increase its time period of charging its wipe mechanic. Morgeth will also spawn many Axion Darts that will track down the players. When Morgeth is closely charging to 100%, a player must grab an Eye of Riven (One should be left on the 2nd wave) and use its Super Ability to restart its wipe mechanic and repeat back on collecting Taken Strength. If players repeat this process, the only difference is that there will be a total of 12 Taken Strength.
For high level players, Morgeth can be easily one phased, with players using the IKELOS_SG_V1.0.1, Whisper of the Worm, and Well of Radiance. Very known places to one phase Morgeth is behind its back, where the IKELOS Shotgun can do major damage to it, or where you spawn at the beginning of the encounter and use Whisper of the Worm to snipe his back. If players struggle with the Axion Darts that spawn, Titan's Code of the Commander Super can block the incoming Axion Darts.
The four Taken Ogres in front of Morgeth must be left alive throughout the entire fight.
The Vault is the 4th encounter that consist of no major boss, but rather a few mechanism that players must solve to reach the final encounter. The Vault includes the following mechanisms that players must know: Symbols, Penumbra, Antumbra and Eye of Riven, later to be explained. The Vault has three plates, corresponding to the three areas that an Eye of Riven will spawn: Stairs (Spawn), Tree and Rocks. To sort the team, there must be three players on the plates and three players (can also be plate players) running the Eye of Riven Weapon (commonly, the people on plates also run, alleviating three spots for add clearing). All three phases of this encounter have a time limit of three minutes, known as the Vault Security Mechanism, that may be reset twice to reset the timer and each phase, while the third slam on the final phase will complete the encounter.
To start this encounter, three people must stand on the three plates around the vault (the large mechanism) in the center of the room. The Vault will portray three symbols for each person standing on a plate, and all three players have a different combination of symbols. There is one large symbol in the center and two smaller symbols left and right of it. For each plate, there is a symbol on the left or right which may be found in the center of another person's set of symbols. The main objective is for each player to deduct which of the two symbols is owned by another player. One of the plate players, commonly stairs, must call out what their middle symbol is and one of the other player must respond if they have that same symbol. If a person has a symbol called out, it will be either left or right of their centre symbol. If a person identifies a symbol on their left, it means their plate requires penumbra, while the symbol being on the right means their plate requires antumbra. Penumbra and Antumbra are essentially "Key Types" that players later will have to slam in the right plates with the Eye of Riven Weapon that could randomly be Penumbra or Antumbra. Once the player responded that their side is Penumbra/Antumbra, that same player will also call out what's their middle symbol and another player will respond if they have it on either Penumbra or Antumbra. Do this until all plates know which "Key Types" their side needs.
It is possible to shorten the communication of the vault by only obtaining the key types of only two plates as there will always be one plate which requires antumbra or penumbra. The key of the final plate may be discovered by process of elimination. For example, if stairs and rocks are both penumbra, it can be concluded that trees requires antumbra. It is still wise to identify all three plates, as a mistake may be identified it it is the case that all three plates are one key type.
On PC, the ideal way to identify the keys needed by each plate by typing them out in chat (i.e "Trees Antumbra" or "T A" for a faster, more efficient call out). On console, it may prove viable to remember what key your plate needs. Ideally, when somebody obtains the Eye of Riven weapon, they identify the key they possess and the person who needs the key asks for their respective plate to be cleansed.
After successfully calling out the plates, one of the rooms, either Stairs, Trees or Rocks will be open and the other rooms will be closed off. It is essential to stay inside the middle room, as people trapped in a closed room will have to run back to the center through a series of tunnels connecting the three rooms. A few enemies will spawn in that room and then an Eye of Riven will spawn that must be defeated. Once defeated, a player must pick up the Eye of Riven Weapon and the room that they are in will be closed off and another room will be open. Players must call out which side is open for the runner so that he/she can exit the room via the appropriate tunnel. When the runner picks up the Eye of Riven Weapon, it will act a key type of either Penumbra or Antumbra. The runner must slam, using the Grenade Button, at the correct plate that was called out at the beginning of the encounter. During this time, a Miniboss Might of Riven will spawn randomly on either rooms and must be defeated before the it reaches to the plate. If this knight ever reaches a plate and slam its sword for a short period of time, all players will die. It is crucial for at least one player to monitor each room for a Might of Riven, as it is more common to wipe due to a knight stealthily sneaking onto a plate rather than a lack of damage. Once the runner has successfully slammed on the correct plate, that runner can no longer pick up the Eye of Riven Weapon until they are revived, the timer runs out or a new vault sequence is initiated. The room that the runner exited from will be the next spawn of Eye of Riven and another player must pick it up. It may also be noted that whichever clockwise direction the rooms are open will repeat. For example, if stairs is open first and rocks become open after killing the eye of riven, the next room to be open after the Eye of Riven at Rock is killed will be trees and subsequently stairs.
It is possible to speed up the vault encounter greatly by using the Tractor Cannon to propulse the Eye of Riven closer to the vault mechanism. Because the rooms do not close immediately after killing an Eye of Riven, it is possible to move the Eye of Riven close to the edge of the main room, in some cases pushing him well into the room, and run back into the center with the riven weapon without having to run through the tunnels. The Tractor Cannon "method" may also prove useful when a mistake occurs, such as slamming an incorrect plate, as the Eye of Riven will continues to spawn until all the plates are cleansed or the timer runs out. It is possible to obtain four Eye of Riven weapons in one cycle by using the tractor cannon mehtod. Keep in mind that the Tractor Cannon will not push Mights of Riven, and will only apply a debuff.
Essentially, players must slam the keys on the correct plate three times, and must repeat this process three times. When the runner picks up the Eye of Riven Weapon, a Miniboss Might of Riven will spawn as explained before, but when the 2nd runner picks up the Eye of Riven, two Miniboss Might of Riven's will spawn and when the 3rd runner picks it up, there will be three. The time limit will restart back to three minutes once all three keys are slammed.
The Mights of Riven must not be allowed to leave their spawn rooms. If they cross the barriers, the challenge fails.
Riven of a Thousand Voices
As soon as everyone steps on a plate, they will begin floating down and come face to face with Riven herself. Once everyone lands, they must split into two groups of three and run into one of the two rooms, marked by either a crystal or a tree. The door will lock after a certain amount of time, so the fireteam must head into their rooms quickly. Everyone should clear adds, beginning with the Hobgoblins. At this point, one of two things will happen: either Riven appears in the room from the black wall, or she does not and an Eye of Riven appears instead.
If Riven shows up in the room, she will use one of two attacks. If the tentacles on the sides of her head extend, someone must lure her into attacking and jump as soon as that tentacle hits the ground. The group should then hit it until she staggers. If her tentacles do not extend, she will breathe fire. Once she finishes spewing fire, her mouth will glow and will be vulnerable to damage. Either way, once she is staggered, two of her ten eyes will glow and the fireteam must take note of them for the other team to shoot, either in PC text chat or console messaging.
If the Eye of Riven spawns in the room, players must kill it. It will drop a Taken Essence which will then be used to cleanse a symbol that will be visible on the lens a player will look through. Another player must head to the back of the room and up a platform, behind a lens and guide them to the symbol they called out, as the Essence holder cannot see them on the ground. Once they are over that symbol, they must hit the grenade button to cleanse it.
Riven and the Eye will switch sides when she is staggered. She will appear in the other room, regardless of whether the symbol was cleansed or not, so both groups must coordinate their staggers and cleanses. When Riven switches over to the other side, the group with her has a small window to damage her and shoot the eyes the other team called out. If the incorrect eyes are shot, the fireteam will wipe, and anything with splash damage will hit other eyes. Once both groups are finished in the rooms, they will head to the back of the room and take a lift up. Riven or the Eye, whichever the opposite of what either group started with, will appear in the second room. Both groups must repeat their processes and take a lift up to the starting room.
Once both groups are in the starting room, Goblins and Ogres will spawn. Both must be taken down quickly, as the Goblins will shield the Ogres, and the latter will knock players back. Riven herself will also appear in the room, and the group must stagger her three times for a total of six eyes. As usual, take note of these eyes in text chat. There will be another small opportunity for damage, and while Riven is being damaged, players must shoot her six eyes. After all six eyes are shot, the Riven will retreat and the fireteam will be affected by the Creeping Darkness debuff. When it reaches ten stacks, they will die. Everyone must run to the starting plates and start the real DPS phase.
The fireteam will float down as they did at the start, but this time you will have an opportunity to deal significant damage. On Riven's body, there are black sores that must be shot at, which will deal a lot of damage once burst, but will spawn an Axion Dart as well. Players must alternate between shooting the darts and her sores, and move around as they're floating down to get clearer shots at her sores and not get blocked off by parts of her body. If the team has not dealt enough damage, they must repeat the process.
If the team has dealt enough damage except for that small segment of her health bar, they will get teleported into the Ascendant Realm and must run up on platforms. Along the way, Phalanxes will spawn and the group's health will gradually deplete. The team must eliminate these Phalanxes and watch their health while running. A Warlock should drop a Healing Rift and/or Divine Protection to keep the group's health up. At the end will be a Taken Strength orb, and only one player has to pick it up for the entire team to be teleported back to the starting room.
Riven will appear once more and will attempt to wipe the team. Everyone must shoot her glowing mouth and kill her. When this is done, everyone must run into Riven's mouth and shoot the blight inside her body. The fireteam must do this quickly, because everyone's health will be depleted over time. Once the blight is destroyed, Riven will be slain, but the raid isn't over yet.
Another unconventional way is to "cheese" Riven with cluster missile rockets. When the fireteam floats down Riven to the two rooms, the fireteam will instead all head to one room, preferably the blue crystal room. Upon entering, they will watch the wall were Riven appears to see if a black shadow will cross. If it does, Riven will not come to this room first and the team stays there. If it doesn't, the team will leave the room and hug a wall, causing the "Joining Allies" countdown to appear, forcing the player back to the main room to go down to the yellow tree room. Either way, you want Riven will come and open her mouth to wipe the team. Instead of shooting the correct eyes (because your team skipped that part), the fireteam will shoot cluster missiles into Rivens mouth. If done with the right debuffs and buffs, Riven will take enough damage to teleport the team to the Ascendant Realm.
Each player cannot shoot the same eye more than once.
The Heart of Riven
At the beginning of the encounter, the Heart of Riven will choose a player to hold it. This player will have the Fate's Chosen buff. As soon as the Fate's Chosen player picks up the heart, everyone must run out of Riven's mouth. That player must keep an eye on the timer on the lower left and count it down from fifteen seconds. As soon as that timer runs out, anyone too close to the player holding the Heart will get sucked inside along with the Heart holder. At the same time, the Heart also emits an aura that protects everyone else from the Creeping Darkness debuff, so everyone must stay close until the last few seconds. If a player dies, they will be sucked into the Heart regardless.
Once a player gets sucked in, the Heart will choose another player. By the time a new player is chosen, the remaining fireteam outside of the Heart should be outside of Riven's body and into a room full of adds. Everyone should use their supers to clear them. Blade Barrage, Hammer of Sol, and Chaos Reach work really well here, as well as Banner Shield to protect the Heart holder. The team will be making their through right hallway (instead of the left leading up to Riven) as well as the Vault. At the Vault, you must head into whichever area is open — either the forest or the pillar area, and take the longest route of side tunnels to stairs.
While this is all happening, the first Heart holder that got sucked inside must grab all of the Taken Strength inside as well as clear waves of adds, including Mights of Riven. The last Taken Strength orb must be left alone until three seconds on the countdown. This will slow down the Heart's beating and reset the Fate's Chosen timer, but this will only work once per player. As the run continues, more players will be teleported in, and more adds will spawn. Just like Morgeth, players can only have two Taken Strength at a time, requiring others to collect them so Fate's Chosen can reset. The number of Taken Strength in the Heart is reletive to how many players are in the Heart.
The runner needs to make their way to the stairs in the Vault and jump down the shaft. They must take the Heart up the stairs, to the bowl between Shuro Chi and Kalli and plant it there to finish the raid.
Wall of Wishes
The Wall of Wishes can be found right before the Kalli encounter. It consists of 21 buttons, when shot, will change to a different symbol. There are fifteen wishes that can be activated for the raid: