Glory of the Midnight Raider

VOIDSPIRE:
Nothing to See Here
Just walk off the map whenever.

The Only Winning Move Is Not To Play
Clear all trash. There will be three glowing banners that anyone can pick up. If someone accidentally picks it up, resetting the boss will respawn them.
Do the 2 soaks on the adds as normal. After the final one, you will be able to place 1 banner down. The goal is to get 3 in a row to win tic-tac-toe. Rinse and repeat until you win. Kill boss

Hungry Hungry Hatchlings
To the right of room, there will be a nest with hatchlings (little versions of Vorasius). When the boss is pulled, you will be able to interact with the nest to pick one up. All players must get one.
During add phase, killing the adds makes them drop pieces of meat. Walking your hatchling over to the meat will cause it to start eating. After eating one piece of meat, it needs time to recharge before eating more. You will need to let it eat 8 stacks of meat. These can be seen by clicking on your hatchling. The pieces of meat remain on the grounds for a very long time. Once every hatchling is full and falls asleep, you can kill boss.

It's Treason Then
Normally, everyone needs to /kneel while targeting Saladbar. This gives a debuff that causes a mirror image of you to appear. When it appears, you must look at it directly until it despawns or you die. These appear for everyone in raid at the same time and has an audio cue. Basically, kill the boss while doing this extra mechanic.
HOWEVER
When everyone kneels to the boss and wipes, the achievement still tracks that as having met the condition of kneeling. Meaning that you can kill boss without kneeling again.
This may get fixed later.

Ready, Set, Snap!
Everyone needs to break their tether within 3 seconds of getting them. This tether occurs after Vaelgor does his Null Beam. You will rinse and repeat this until both bosses are dead. Don't premove, it does not help.

We used an achievement tracker addon to keep track if we failed. HOWEVER, it was not super reliable. Our experience was that the addon kept track each time the tether came out. BUT it told us for one of them that we had FAILED. But someone in our group noticed the checkmark, for condition being met on the actual WoW achievement interface, remained despite what the addon said. We decided KILL the dragons and we did get the achievement!
Note: Dead persons might cause achievement to fail

Aura Farming
To the right of the staircase, there will be a book that anyone can interact with. Everyone must interact with this book and get the debuff to farm aura. When one of the paladins reaches max energy and uses their aura, linger inside the aura to get a buff. Do these three times and eventually, you will get a blueish/purpleish circle around you showing that you achieved maximum aura. Kill bosses once everyone has this (it will show as a buff).

We Will, In Fact, See It Again
After you kill the paladins, there will be a puddle next to the orb that takes you to the final boss, stand in it until you get a 10 minute debuff. You will will also see an extra action button. After killing the 3 mini bosses, you will need to use your extra action button in the intermission. Get somewhat close to the center and use the extra action. Once EVERYONE has done this, a Fleshy Monstrosity will eventually appear in P2. NUKE this add down quickly. If left alive for too long, it will cause your attacks to hurt allies. Once P2 is over, you will need to do what you did in the first intermission again. Get close to the center and use your extra action button. After EVERYONE has done this, the boss is safe to kill. There will NOT be another add in P3.

The Dreamrift
Falling Between The Quacks
On the first platform where everyone enters the raid, Sergeant Quackers will be northwest of the platform behind a boulder. One person needs to interact with him to send him over to the 2nd platform.
Fly over to the 2nd platform and clear adds. Take note of Sergeant Quackers who is standing on the left.
Start the boss fight, when the 1st group enters the rift by getting hit by the soak mechanic, Sergeant Quackers needs to be interacted with to pluck corrupted feathers off him. You can focus on him to keep track of corrupted feathers remaining. Once both soak groups have done this successfully, you can kill the boss normally.
HOWEVER, please do these things to make life easier for yourself and your team:
1. Place a marker on him and set focus on him to make him easier to find (pinging your focus, pings him!)
2. Bind your interact key: OPTIONS -> Enable interact key -> Bind it to something
He runs fast all over the place and only stops for like a second. Spamming the interact key while being next to him is the easiest way to pluck him. He makes a noise!
3. Nuke the adds in the rift first. This is to prevent squishies from aggroing mobs and because we had many wipes due to the big add not dying
Notes: Each soak group has TWO opportunities to pluck the corrupted feather, so it is okay if someone misses it on their first respective soak
Everyone needs to pluck the feather. You can tell if you plucked the feather successfully if you see a feather rotating around your body

MARCH ON QUEL'DANAS
Eggsistential Crisis
Warning: Picking up the egg is buggy. It respawns when the boss respawns. Might need to wipe until a tank can pick it up and toss it to other tank.
Clear all the trash up to 1st boss. To the left, up the stairs, there is an egg. A tank should pick this up. Technically, anyone can pick this egg up but holding it gives the carrier a ramping DoT unless it is passed to another. Because of this, we had our tanks serve as the egg bearers. The gist of this achievement is to infused the egg with both light and void energy until it reaches 100% in each category. However, you can only do one category from 0 to 100 at a time. Getting hit with the opposing energy will reset progress. The egg can be infused by boss attacks, standing in puddles, and the intermission. Void tank should toss egg to light tank once they are done (MACROS HELP ALOT). Once the egg has been imbued with both energies, do the fight normally.

All the Things She Said
To the right of the hallway, there is a torch. Interact with it. Do fight as normal until P3. In P3, drop one crystal to defend against L'ura's The Dark Archangel cast. Move to the left as a unit. In the space you walked out of, there will be 3 adds that need to be interrupted before they disappear. Dodge the laser mechanic, stack and use another crystal to defend against her next cast. Rinse and repeat until 12 adds are interrupted. Kill boss. Recomm

DreamRift
Falling Between The Quacks-
Interact with quackers on the platform that you enter the raid on. Give him a marker, when the trash is cleared the boss will spawn and quackers will be on the boss platform. Upon boss pull he will attack the boss, when he summons the adds in the rift quackers will be found in the rift only. Every player from the raid must interact with quackers to remove a corrupted feather. Once every player has done so he will escape the rift and attack the boss. At this point the boss can be killed normally.

The Voidspire

Boss 1 (Imperator Averzian)
The Only Winning Move Is Not To Play
Before the 1st boss are 3 banners, 3 separate players must pick up the banners. During the boss fight the boss will make spawn 3 adds and then a soak mechanic. Use the soak mechanic to kill 2 of the adds while the last add remains as a ball. You want to deny 3 in a row (think tic-tac-toe). Use the banners after the last soak, once you have 3 banners in a row you "win" and the achievement turns white. You can then kill the boss. Note if the boss gets 3 in a row he will enrage.

Boss 2 (Vorasius)
Hungry Hungry Hatchlings
When the boss is pulled a barrel full of hatchlings will spawn on the right side of the arena. Everyone in the raid will need to grab a hatchling (including tanks). During the fight Blistercreep adds will spawn when they die they leave a corpse on the ground that the hatchlings eat, once the hatchlings eat 8 corpses they will fall asleep, once everyone's hatchling is asleep kill the boss for the achievement to pop. For tactics, I suggest everyone apart from 1 tank stand on the barrel as the boss is pulled. Grab a hatchling then rush to the center, make sure to allow the tank to grab one. When using the Blistercreep adds to break walls kill them in melee so that when melee dps their hatchlings can feed.

Boss 3 (Fallen-King Salhadaar)
It's Treason Then
kneel before the boss before the fight begins, you are given a debuff which adds an additional mechanic similar to delve Kyeveza. A shade of yourself will spawn frequently. When it spawns you must face it or you will die, complete the fight with the mechanic people can die and still get the achievement.

Boss 4 (Vaelgor & Ezzorak)
Ready, Set, Snap!
When Null beam goes out the tether from the orb needs to be broken within 3 Seconds. best way to do this is WAIT for the tether to be on you then use any kind of movement speed to break it fast...(DO NOT TRY TO PRE BREAK IT) have to do this every time it goes out -- will need some one to track this achievement and make sure its white before the boss dies--

Boss 5 (Lightblinded Vanguard)
Aura Farming
Before the bosses arena on the right side a small book lies on the ground. Everyone in the raid will need to click on the book to be granted a debuff "Aura Farming." Throughout the fight the bosses will create an aura everyone in the raid should stand in the aura for a brief moment to upgrade there aura. Once all 3 auras have been absorbed by everyone you can kill the boss as normal. Care for mechanics as they will still hurt. Additionally if you have a higher aura than someone else in the raid you will stun them until they match your aura. So clear a way to the aura so they can grab it uncontested.

Boss 6 (Crown of the Cosmos)
We Will, In Fact, See It Again
To complete this achievement before the final boss near the teleporting orb is a small puddle that grants a debuff, you must get 10 stacks of the debuff to get a lump of flesh, which gives you an extra action button to throw it and lose some hp. Once you kill the first 3 minibosses Alleria will toss you up in the air and pull you to the center. Walk towards the center and toss the lump of flesh in. Once everyone throws the lump of flesh in a fleshy monstrosity will spawn. (Focus this mob as he has a convert mechanic that makes you dmg those around you.) after this you will be holding a chuck of flesh and will have to throw this in to the void hole in the center in the 2nd intermission (DONT FALL IN)

March on Quel'Danas

Boss 1 (Belo'ren, Child of Al'ar)
Eggsistential Crisis
EGG located at 42, 44 to the left of where the boss is. have tank hold on to it (was bug and would not let us throw it but could just heal tank the whole time) get hit with light to infuse with light then hit with void to infuse with void when done kill boss easy

Boss 2 (Midnight Falls)
All the Things She Said
nteract with the void torch in the room in front of the boss, on the right side, before starting the fight. In P3 3 adds will spawn in the dark frontal the boss does, kick them before they despawn...do this 4 times 4x3=12 kill the boss!

Thanks to Melasoma and Revenant209 on all the info provided to make this full guide

Ran out of characters. A few more points on last achievement. I highly recommend assigning 5 people to be the shard carriers. Then coordinate who drops the shard when in P3 as you will need at least 4 of these to not wipe against L'ura's cast. So, as P2 wraps up, everyone stack on 1 spot EXCEPT for the shard bearers. They should stand slightly apart because L'ura will cause their shard to drop when P3 starts. Shard bearers should collect their shard and stack with the whole group again. 1st person drops their shard before L'ura's first Dark Angel cast. Interrupt adds. Survive. Rinse and repeat