The Dread Lords have worked for eons to bring Zovaal's plan to completion. Now, on the brink of their master's victory, they only need to complete one final task to ensure none are left to resist the new order.
During this encounter you will be fighting against both Dreadlords at the same time. They will slowly fill the encounter area with 
Slumber Clouds and when they reach 100 Energy each Dreadlord use their ultimate ability.
Mal'Ganis will use 
Unto Darkness which will turn both Dreadlords into swarms of insects which will deal large amounts of raid damage, however both bosses will take 100% more damage from the raid.
Kin'tessa will use 
Infiltration of Dread which will make the entire raid hostile to each other and both bosses will hide inside players. Identify the players who have the dreadlords hidden in them and kill them to end the phase. Most people will see the same two players as the ones with the bosses hidden in them, however the players with the bosses will see different people in an attempt to throw you off. Follow the majority instead of the vocal few.
When either boss dies their corpse will deal increasing amounts of raid damage until the other boss dies with 
Rampaging Swarm. Kill both bosses at a similar time.
Two Slumber Cloud spawn in the room after each 100 Enery Ability and on the pull at player locations. If a player touches a cloud they will be put to sleep for 8 seconds.
Cloud of Carrion is applied to players as the fight goes on. This will deal increasing damage per tick. This can be passed to another player by them having them run into the Green Circle around the player with the Cloud of Carrion.
Biting Wounds is applied to players who remove the debuff, increasing their damage taken from Cloud of Carrion for 8 seconds.
Fearful Trepidation - Two players will have this applied to them and anyone within these when it expires will be feared.
Fearful Trepidation can be used to remove Cloud of Carrion permanently from the fight and you will not be feared.
This will cause small swarms to project from the player based on the direction they are facing. If any player makes contact with these they will receive the Cloud of Carrion debuff so it is important that no player is hit by these.
Manifest Shadows - An Inchaote Shadow will spawn in the room. Let it reach full health from 
Ravenous Hunger casts and then kill it.
Ideally your raid should have a Death Knight player 
Death Grip this add onto the bosses when it reaches full Health.
Your role as a tank on this encounter is to move the bosses away from Slumber Clouds and keep them faced away from any other player (including your co-tank).
Mal'Ganis will attack the tank and all targets in front of him with 
Leeching Claws and apply 
Opened Veins which reduces healing received.
If Leeching Claws hits a target which has Opened Veins 10% health will be restored to Mal'Ganis.
Kin'tessa will attack the tank and all targets in front of her with 
Anguishing Strike and apply a stacking Shadow DoT.
Unto Darkness - When Mal'Ganis reaches 100 Energy both bosses will deal high amounts of raid damage for 20 seconds and take 100% more damage.
Any spec with a 2 minute AoE damage cooldown should save them for this phase for additional damage.
[Heroic] After each use of Unto Darkness Mal'Ganis gains a stack of 
Decay Mastery which increases damage dealt by 10% and increase the tick rate of Cloud of Carrion.
Infiltration of Dread - When Kintessa reaches 100 Energy the raid will become hostile to each other and both dreadlords will be hiding on players in the raid. Some of your raid are able to see the Dreadlords above players. Call out who you can see and once you have reached a consensus as a raid, kill those players to end the phase.
Two players will see different players from everyone else, these are the ones you have to kill! Once you kill them, they get an immunity aura preventing them from actually dying. Tanks are never chosen.
If you accidentally kill a wrong player, they are just dead.
[Heroic] After each use of Infiltration of Dread Kin'tessa gains a stack of 
Shadow Mastery which increases her damage dealt by 10%, and increases the size of Slumber Clouds.
Mal'Ganis & Kin'tessa Swing Timers: 1.5s (Curse of Weakness 1.8s)
Leg Sweep can be used to prevent the Manifest Shadows from casting once it has reached full Health.
Ring of Peace can be used to bring in the Manifest Shadows once it is on full health.
Do not save 
Niuzao for the Unto Darkness phases as you are not taking physical damge during this moment so the damage it deals will be lower than if you used it during active boss tanking phases.
Sigil of Silence can be used on the Manifest Shadow add when they are on full Health to prevent them from casting.
Avenger's Shield should be thrown on Manifest Shadow add when they are on full Health to prevent them from casting.
Hammer of Justice can also be used on the Manifest Shadow add when they are on full Health to prevent them from casting.
Blessing of Spellwarding can be placed on a player with Cloud of Carrion during Unto Darkness to keep them healthy.
Spell Reflection is best used to mitigate damage from Kin'tessa's Slash and Unto Darkness.
Anguishing Strike and Leeching Claws are both blockable.
Rallying Cry is best used to help the raid with the damage taken during the swarm in Unto Darkness.
Stampeding Roar is useful to help the raid get back into position after Infiltration of Dread.
Anti-Magic Shell to mitigate damage from Kin'tessa's slash
Anti-Magic Zone is best used to mitigate raid damage taken for the raid during the swarm in Unto Darkness.
Death Grip the Manifest Shadows add to the boss once they reach full health.
Gorefriend's Grasp can be useful to grip the Manifest Shadows add closer to boss if Death Grip does not get it all the way to the boss.
Necrolord Death Knights should save 
Abomination Limb for the swarm in Unto Darkness as it will deal increased damage during this phase. Additionally, the phases are just over 2 minutes apart so you will have it available for each one.
During this encounter you will be fighting against both Dreadlords at the same time. They will slowly fill the encounter area with Slumber Clouds and when they reach 100 Energy each Dreadlord use their ultimate ability.
Mal'Ganis will use Unto Darkness which will turn both Dreadlords into swarms of insects which will deal large amounts of raid damage, however both bosses will take 100% more damage from the raid.
Kin'tessa will use Infiltration of Dread which will make the entire raid hostile to each other and both bosses will hide inside players. Identify the players who have the dreadlords hidden in them and kill them to end the phase. Most people will see the same two players as the ones with the bosses hidden in them, however the players with the bosses will see different people in an attempt to throw you off. Follow the majority instead of the vocal few.
When either boss dies their corpse will deal increasing amounts of raid damage until the other boss dies with Rampaging Swarm. Kill both bosses at a similar time.
Bloodlust/Time Warp/Heroism is best used either for the first Unto Darkness phase or the second. The first is easier as it will have all cooldowns aligned, the second can be better but this is dependant on how quickly you do the Infiltration of Dread as if you are very quick 3 minute cooldowns may not be back.
Everyone should have the Aeon Remnants - Among Us Helper WeakAura. There is a section below in this page detailing how it works as it makes the Infiltration of Dread mechanic easier to handle as there is less communication clutter.
DPS players should aim to have cooldowns for each Unto Darkness phase as the bosses will take 100% more damage in this window.
1 Minute cooldowns that are not Kyrian Covenant abilities (with Mikanikos) should be saved for the first Unto Darkness and then used on cooldown thereafter.
2 Minute DPS cooldowns should be saved for each one.
3 Minute cooldowns will be available for every other one.
Each Unto Darkness will deal more damage than the previous one in Heroic/Mythic so your Healer cooldowns should be planned with this in mind.
Likewise as many Healer cooldowns are 3 minutes they should be staggered so you don't blow everything on the first one and have very few for the second one.
You should have pre-assigned players to bring the Manifest Shadows into melee range. If you have a Death Knight then then they should use Death Grip to bring it into melee range. However not all adds will be in Death Grip range. When this is the case ranged players with Knockbacks should help the Death Knight and push it closer.
Slumber Cloud - When you pull the boss and after each 100 Energy Ability this will be cast creating two clouds at player locations. If a player touches a cloud once it has fully formed they will have the 
Unselling Dreams debuff applied to them and put to sleep.
Clouds are always placed on one melee player and one ranged player and these can be baited to be in more favourable locations. A small loss of melee DPS uptime is better than having to move the bosses more and having a clearer room. Ranged should never be in front of the boss movement path.
Cloud of Carrion - As the fight goes on several players will have this debuff applied to them from Mal'ganis. This will deal increasing damage per tick. This can be passed to another player by them having them run into the Green Circle around the player with the Cloud of Carrion.
When Cloud of Carrion has been removed, the player who held it will receive the Biting Wounds debuff, increasing their damage taken from Cloud of Carrion for 8 seconds.
Fearful Trepidation - Two players will have this applied to them and anyone within these when it expires will be feared.
Additionally Fearful Trepidation can be used to remove Cloud of Carrion permanently from the fight and you will not be feared.
This will cause small swarms to project from the player based on the direction they are facing. If any player makes contact with these they will receive the Cloud of Carrion debuff so it is important that no player is hit by these.
Manifest Shadows - An Inchaote Shadow will spawn in the room. It will have the 
Incomplete Form buff which prevents it from dying, however this buff is removed when it reaches full Health. It will cast Ravenous Hunger repeatedly and each cast will deal raid wide damage and heal the add by 15% per cast.
Ideally your raid should have a Death Knight player Death Grip this add onto the bosses when it reaches full Health.
Your role as a tank on this encounter is to move the bosses away from Slumber Clouds and keep them faced away from any other player (including your co-tank).
Tanks should aim to keep both bosses stacked on top of each other and stand at angles which make them safe from the cleave of the other boss and keep the melee/ranged safe as illustrated below.
Mal'Ganis will attack the tank and all targets in front of him with Leeching Claws. This will apply Opened Veins to players hit which reduces healing received by 25% for 20 seconds.
If Leeching Claws hits a target which has Opened Veins 10% health will be restored to Mal'Ganis.
Kin'tessa will attack the tank and all targets in front of her with Anguishing Strike. This will apply a stacking debuff to players hit which deals Shadow damage over 18 seconds.
Unto Darkness - When Mal'Ganis reaches 100 Energy both bosses will deal high amounts of raid damage for 20 seconds and take 100% more damage.
Any spec with a 2 minute AoE damage cooldown should save them for this phase for additional damage.
[Heroic] After each use of Unto Darkness Mal'Ganis gains a stack of Decay Mastery which increases his Physical Damage dealt by 10%, increases the tick rate of Cloud of Carrion, and when Cloud of Carrion is removed from a player more clouds are projected from players.
Infiltration of Dread - When Kintessa reaches 100 Energy the raid will become hostile to each other and both dreadlords will be hiding on players in the raid. Some of your raid are able to see the Dreadlords above players. Call out who you can see and once you have reached a consensus as a raid, kill those players to end the phase.
Two players will see different players from everyone else, these are the ones you have to kill! Once you kill them, they get an immunity aura preventing them from actually dying. Tanks are never chosen.
If you accidentally kill a wrong player, they are just dead.
[Heroic] After each use of Infiltration of Dread Kin'tessa gains a stack of Shadow Mastery which increases her Shadow Damage dealt by 10%, and increases the size of Slumber Clouds.
The Infiltration of Dread mechanic can be made easier with the use of a WeakAura.
Wago Link - Aeon Remnants - Among Us Helper
For this WeakAura to function every player in the raid should have it and it will attach a voting frame to nameplates. People who can see other infiltrators should vote on who they can see and when a player has three or more votes this is your indicator to attack that player. This is because the players with the bosses in them will be able to see other targets than the rest of the raid so it's a very easy way of identifying who the kill targets are.
Mal'Ganis & Kin'tessa Swing Timers: 1.5s (Curse of Weakness 1.8s)
Leg Sweep can be used to prevent the Manifest Shadows from casting once it has reached full Health.
Ring of Peace can be used to bring in the Manifest Shadows once it is on full health.
Do not save Niuzao for the Unto Darkness phases as you are not taking physical damge during this moment so the damage it deals will be lower than if you used it during active boss tanking phases.
Sigil of Silence can be used on the Manifest Shadow add when they are on full Health to prevent them from casting.
Avenger's Shield should be thrown on Manifest Shadow add when they are on full Health to prevent them from casting.
Hammer of Justice can also be used on the Manifest Shadow add when they are on full Health to prevent them from casting.
Blessing of Spellwarding can be placed on a player with Cloud of Carrion during Unto Darkness to keep them healthy.
Spell Reflection is best used to mitigate damage from Kin'tessa's Slash and Unto Darkness.
Anguishing Strike and Leeching Claws are both blockable.
Rallying Cry is best used to help the raid with the damage taken during the swarm in Unto Darkness.
Stampeding Roar is useful to help the raid get back into position after Infiltration of Dread.
Anti-Magic Shell to mitigate damage from Kin'tessa's slash
Anti-Magic Zone is best used to mitigate raid damage taken for the raid during the swarm in Unto Darkness.
Death Grip the Manifest Shadows add to the boss once they reach full health.
Gorefriend's Grasp can be useful to grip the Manifest Shadows add closer to boss if Death Grip does not get it all the way to the boss.
Necrolord Death Knights should save Abomination Limb for the swarm in Unto Darkness as it will deal increased damage during this phase. Additionally, the phases are just over 2 minutes apart so you will have it available for each one.
Slumber Clouds are now permanent.
Manifest Shadows adds gain 
Fully Formed when they are at full health increasing their damage dealt, they are unable to be CC'd once they are at full Health, and they now only heal for 11% per cast (down from 15%) meaning that they will not reach full health until the bosses begin their 100 Energy Abilities.
After each 100 Energy Ability the boss gains a buff increasing the power of them for 50 seconds.
Mal'Ganis gains 
Aura of Carrion which increases the tick rate of Cloud of Carrion and allows him to cast an empowered Cloud of Carrion which shoots swarms from his body. These act the same as when a player removes them with Fearful Trepidation so the raid will need to be mindful of this and melee will need to move out of melee range during this cast to avoid being hit.
Kin'tessa gains 
Aura of Shadows which fears players who are not within 8 yards of another player. If a player gets feared a group of two players will need to come and rescue them.
In addition to previous assignments, every player in the raid should be very mindful of Slumber Cloud baiting as they are not removed on Mythic and one bad bait will leave you with less encounter space.
A strategy will be added once I have defeated the encounter on Mythic.