Xavious final boss

Hey guys – given we’re going to murdering Xavius on Sunday night, this should hopefully be useful.
There are a lot of things to know about this fight – but in general each person will have a maximum of 2 things to know about in each phase.

Corruption:

So – first off – throughout the entire fight we’ll be dealing with corruption – most of Xavius’ abilities cause corruption to those whom they hit - this fight is about keeping that corruption under control.
Maxing out on corruption will give you a buff that increases the damage and healing that you do by 150% for 20 seconds.  When this buff expires you’ll be mind controlled and the raid will have to kill you – note that if you die in this way you cannot be battle-ressed, as you’ll return with the same corruption you had before and promptly be mind controlled again.

The Dream:

To help us with controlling corruption we have the spirit of the Ysera, who will - twice in the fight - put half of the raid into the dream.  Those placed into the dream will be randomly selected, balanced by roles.  On the second occasion all of those were not chosen for the first time will be placed in the dream, thus everyone will be in the dream once in the fight.
When placed into the dream you become a “Dream Simulacrum”.  Taking lethal damage or maxing out on corruption will cause you to exit the dream, and return to the state you were in prior to entering it – this means that you’ll regain used cooldowns and return to your old mana value.
The players in the dream therefore have the job to soak up corruption causing abilities – as we don’t know who’ll be in the dream it’s important that everyone know what the dreamers have to do in each phase.

Phase 1:

Phase 1 lasts until 65% health.  Half of the raid will be placed in the dream at 95%.

In each phase Xavius will be tanked facing away from the Raid.

During phase 1 the raid will remain together, quite close into Xavius – we don’t need to be on top of each other but it helps with the mechanics of this phase if we stay fairly close together.
Throughout this phase Xavius will use “Nightmare blades” every 15 seconds, this will target 2 players, and, after 4 seconds, Nightmare blades will burst from the ground along the line intersecting them.  To handle these blades the 2 targets will move to the right of the raid, orienting by the direction that Xavius is facing.

Every 20 seconds in this phase Xavius will summon an add.  Normally this is a “Lurking Terror”, which will appear beneath a random non-dreaming player.  It will fixate on a target and move towards them.  When intercepting any player it will deal them damage and give them 20 corruption.  To deal with this, when this is summoned the raid will move away from the add, and a dreaming player will move in to intercept it and take the corruption.  After the add has been dealt with, the raid will stack back up.

However, the 3rd and 7th time Xavius summons an add he will instead use “Manifest Corruption” – this ability deals heavy raidwide damage and summons a large add called a “Corruption Horror”.  This add has a powerful frontal cone attack that causes corruption in front of it (don’t stand in front of it). Every 20 seconds it will use “Corrupting Nova”- dealing heavy raidwide damage and giving 5 corruption to everyone.
This large add will be tanked by the dreaming tank, next to Xavius but facing away from both the Xavius tank and the raid.  This add is public enemy number one and must be killed ASAP, pop cooldowns and burn it when it spawns, we need as few  corrupting nova casts as possible.

In every phase of this fight the healers and tanks will have to deal with a stacking debuff on the tank.  In phase 1 this is called “Darkening Soul”.  Xavius will place it on his current tank every 8-10 seconds.  The debuff deals heavy damage and has an infinite duration.  This debuff can only be dispelled, and should be dispelled at 3-4 stacks.  However – dispelling this debuff causes a large amount of damage in a 25 yard AoE centred on the tank.  It will also give 25 corruption to the dispeller.  

To handle this when the tank decides that its dispelling time they will call for the other tank to take Xavius and move to the left of the arena, again orienting by Xavius ‘ facing.  (this should be to the tank’s right).  When they’re far enough away the dreaming healer will dispel the debuff from them.

Difficulties can arise from this with the dreaming tanks need to also tank the Corruption Horror add – this may result in the non-dreaming tank gaining an uncomfortable number of stacks whilst that add is killed – these adds spawn at known times so the only difficulty is that we don’t know who the dreaming tank will be.  Ideally the dreaming tank will be hitting 3-4 stacks just prior to the Corrruption Horror spawning – but it’ll be fun to see how this goes in practice.  

So, to summarise phase 1:

The raid will stack behind Xavius – when targeted by “Nightmare Blades” those linked will move to the right, ensuring that the line between them does not move into the group.
Every 20 seconds adds will spawn.  “Lurking Horror” will spawn beneath a player and fixate on a player, whom they will follow.  A dreaming player will intercept the add to soak the corruption from their attack.
The 3rd and 7th adds will be large “Corruption Horror” – when these are summoned they will deal heavy raidwide damage. The dreaming tank will pick these up and tank them next to Xavius.  These adds must be focused and killed ASAP.

Throughout the phase tanks will gain stacks of “Darkening Soul” which deals heavy damage. At 3-4 stacks the tanks will switch, and the tank with the debuff will move away to Xavius’ left, where they will be dispelled by the dreaming healer, who will gain 25 corruption.

Phase 1 will end at 65%.  We should not push Xavius to this point if any Corruption Horrors are alive.

Phase 2:

Phase 2 lasts from 65% to 30%.  At 60% the half of the raid who were not in the dream in phase 1 will enter the dream.  In Phase 2 Xavius will no longer use Nightmare Blades or summon Lurking or Corruption Horrors.  Additionally the debuff he uses on tanks will change.

For phase 2 the raid will spread out more.  The dreaming dps will remain behind Xavius, stacked up, while the non-dreamers will move to the flanks.
Every 30 seconds in phase 2 a non-dreaming player will be targeted for “Corruption Meteor” -an AoE ability which will follow them around.  The Meteor deals a lot of damage and also gives 40 corruption. This is, however, spread between all those in the AoE. The targeted player will take this ability to the dreamer group behind the boss to share the damage and corruption with them, after it has hit, they’ll return to their old position.

This would be simple to cope with if it weren’t for the adds that Xavius summons throughout phase 2.  Every 40 seconds he will summon a number of “Inconceivable Horrors”.  These will appear at the edges of the room and must be killed before reaching Xavius.  If they reach him they do regular raidwide damage and corruption.  When killed these adds spawn a pool of “Tainted Discharge”.  This pool must be soaked up by a dreaming player or else it will shortly spawn another Horror.

In phase 2 Xavius will no longer use “Darkening Soul” on tanks, he will instead use “Blackening Soul”.  It is similar to “Darkening Soul” in most aspects, however dispelling it does not cause a large AoE, but instead causes the tank to gain the “Blackened” debuff, which increases the physical damage they take by 150% for 30 seconds.  Additionally, when it is dispelled a pool of “Tainted Ground” will spawn at the tanks feet, and must be soaked by one of the dreaming dps.

Every minute in this phase Xavius will use “Nightmare Infusion”, which will cause his next 6 melee attacks to give 5 corruption each, for a total of 30 corruption.  The dreaming tank should taunt Xavius for this skill.
So, to summarise phase 2:  

Dreamers stack up, non-dreamers spread out a bit.

Corruption Meteor should be taken to the dreamers group to allow them to soak as much corruption as possible – this is their first priority.

Kill Inconceivable Horrors ASAP – they must not reach Xavius.  Killing them will create a patch of Tainted Ground – this should be soaked up by a dreamer.

Throughout the phase tanks will gain stacks of Blackened Soul, similar to phase 1 they should be dispelled at 3-4 stacks.  Dispelling this will spawn a patch of Tainted Ground, which must be soaked by a dreaming dps. It will also prevent them from tanking for 30 seconds due to Blackened. Dispelling this debuff will give the dispeller 25 corruption - it should therefore be handled by the dreaming healer.  
Tanks will also have to handle Nightmare Infusion, which will cause Xavius’ next 6 attacks to cause corruption – Xavius should be tanked by the dreaming tank for the duration of this effect.

Phase 2 will end at 30%.  We should not push to this point without ensuring all “Tainted Ground” has been absorbed.

Phase 3:

Phase 3 is the final phase of the fight, it begins at 30%.  Phase 3 is a race – we need to kill Xavius before we are overwhelmed by the corruption his abilities cause, which we no longer have any methods to soak.
Throughout phase 3 Xavius will reuse the “Nightmare Blades” and “Corruption Meteor” abilities of phases 1 and 2.  “Nightmare Blades” we still move out to the right on, however with “Corruption Meteor” all dps should stack on the meteor target – melee included – to spread the corruption as much as we can.  

Every 20 seconds in phase 3 Xavius will cast “Writhing Deep”.  This ability will summon a number of tentacles around the arena.  These tentacles regularly use an ability on a random target which gives 3 corruption and causes a moderate amount of damage, however, it is not possible to kill all of these tentacles and also kill the boss.  Success in this phase of the fight relies on finding the balance between killing tentacles and damaging Xavius.

To aid with keeping the tentacles under control, the tanks will move Xavius towards any concentrations of tentacles to enable us to cleave them down whilst still focusing the boss.  As the room is totally featureless this might cause problems with nightmare blades, etc. just remember that right and left are set by Xavius’ facing. The ranged group should also make an effort to stay fairly together and fairly close in to Xavius’ back.

Xavius continues to use “Blackened Soul” on his tank during this phase.  Healers should alternate which of them dispels during this phase to keep corruption as low as possible.  
He will also continue to use Nightmare Infusion throughout this phase.  The 6 strikes of this ability should be soaked by the tank with the lowest corruption.

Phase 3 really is a race against time.  Use everything you have, try and keep your corruption down, kill the fucking boss.