This guide is intended to provide a comprehensive description of theencounter with Immerseus in Siege of Orgrimmar. It is targeted at anyonewho desires to understand the fight mechanics.

This guide is updated for World of Warcraft MoP 5.4.

Immerseus is the first boss in the Siege of Orgrimmar raid instance. This isan encounter that is quite simple as far as mechanics are concerned, and which willmore likely test your raid's gear level.

1. General Information↑top

2. Loot↑top

2.1. Armor

Item Name	Armor	Slot	Main Stats
Hood of Swirling Senses (LFR, Flexible, Heroic)	Cloth	Head	Intellect
Ichor-Dripping Shoulderpads (LFR, Flexible, Heroic)	Cloth	Shoulders	Intellect/Spirit
Bolt-Burster Grips (LFR, Flexible, Heroic)	Cloth	Hands	Intellect/Spirit
Hood of Blackened Tears (LFR, Flexible, Heroic)	Leather	Head	Agility
Bracers of Purified Spirit (LFR, Flexible, Heroic)	Leather	Wrists	Intellect
Salt Water Sandals (LFR, Flexible, Heroic)	Leather	Feet	Intellect
Soul-Soaked Gloves (LFR, Flexible, Heroic)	Mail	Hands	Intellect
Puddle Punishers (LFR, Flexible, Heroic)	Mail	Feet	Agility
Greatbelt of Living Waters (LFR, Flexible, Heroic)	Plate	Waist	Intellect
Waterwalker Greatboots (LFR, Flexible, Heroic)	Plate	Feet	Intellect
Chestplate of Congealed Corrosion (LFR, Flexible, Heroic)	Plate	Chest	Strength
Bubble-Burst Bracers (LFR, Flexible, Heroic)	Plate	Wrists	Strength/Hit
Corruption-Rotted Gauntlets (LFR, Flexible, Heroic)	Plate	Hands	Strength/Mastery
Pauldrons of Violent Eruption (LFR, Flexible, Heroic)	Plate	Shoulders	Strength/Parry
Bracers of Sordid Sleep (LFR, Flexible, Heroic)	Plate	Wrists	Strength/Dodge
Treads of Unchained Hate (LFR, Flexible, Heroic)	Plate	Feet	Strength/Parry

2.2. Weapons

Item Name	Type	Main Stats
Trident of Corrupted Waters (LFR, Flexible, Heroic)	Staff	Agility
Encapsulated Essence of Immerseus (LFR, Flexible, Heroic)	One-Hand Mace	Strength/Dodge

2.3. Amulets, Cloaks, Rings, and Trinkets

Item Name	Type	Main Stats
Immerseus' Crystalline Eye (LFR, Flexible, Heroic)	Amulet	Agility
Cloak of Misguided Power (LFR, Flexible, Heroic)	Cloak	Intellect/Hit
Seal of Eternal Sorrow (LFR, Flexible, Heroic)	Ring	Intellect/Spirit
Purified Bindings of Immerseus (LFR, Flexible, Heroic)	Trinket	Intellect/amplifies damage and healing

3. Overview of the Fight↑top

The Immerseus encounter has two phases that alternate until the bossdies.

Immerseus has a Corruption resource bar, which starts out at 100 at thebeginning of the fight, and which then decreases progressively as the fightgoes on, based on actions performed by your raid. Immerseus dies when hisCorruption level reaches 0.

The Immerseus Phase is the phase in which the fight starts and itconsists in fighting against Immerseus himself, who is stationary in thecenter of a circular arena. When Immerseus reaches 0% health (something thatwill happen quite quickly, since he has a small health pool), he will splitinto many adds, and this will trigger the second phase.

The Split Phase starts when Immerseus reaches 0% health. The bosssplits into many small adds (some friendly, some hostile) which then slowly movetowards the center of the arena. The friendly adds can be healed, and thehostile ones can be damaged and killed. When all the adds have been accountedfor (having been healed, killed, or having reached Immerseus), the SplitPhase will end, and the Immerseus Phase will re-start.

Each add killed or healed during the Split Phase removes 1 point ofCorruption from the boss, and when the Immerseus Phase restarts, the healthpercentage of the boss will be equal to his Corruption level. The implicationsof this are twofold:

• You need to bring the boss to 0 Corruption to kill him.
• The Immerseus Phase will be shorter and shorter as the fight goes on.

Videos:

• PTR Preview —a short overview of the boss, based on PTR testing, which is extremelyuseful for getting a rough understanding of the fight;
• Video Guide— a video guide of the boss, based on live-realm experience.

4. Class-specific Advice↑top

On our forums, we are maintaining threads with class-specific advice for each of thefights of Siege of Orgrimmar. So, make sure to check them out, and if you have things toshare, do not hesitate to contribute!

Class	Forum Threads
Death Knight	Blood Frost/Unholy
Druid	Balance Feral Guardian Restoration
Hunter	All specs
Mage	All specs
Monk	Brewmaster Mistweaver Windwalker
Paladin	Holy Protection Retribution
Priest	Discipline Holy Shadow
Rogue	All specs
Shaman	Elemental Enhancement Restoration
Warlock	All specs
Warrior	Arms/Fury Protection

5. Preliminary Information↑top

There are a few things we need to explain before we can look at eachindividual phase of the fight.

5.1. The Room

The arena where you fight Immerseus is a large circular room. Immerseus islocated in the center, where he is stationary. This central area, whereImmerseus is located, is covered in water, and, as we will see later on,players cannot stand in this central area (they get damaged and knockedback).

7 streams of water divide the room into 7 sectors. This division is purelyvisual, however, having no mechanical ramifications whatsoever. Players canwalk over these streams of water freely.

5.2. Adds and Corruption Level

Regarding mechanics, we would like to present to you the way in whichthe boss' Corruption resource works, and how this interacts with the addsthroughout the fight.

As we mentioned before, the boss has a Corruption bar that starts at 100.At the start of each Immerseus Phase (except for the first one), the boss'Corruption will be lower, depending on how many adds have been successfullydealt with. Each add that is healed or killed, respectively, will remove 1point of Corruption from Immerseus.

Additionally, the composition of the add set-up depends on Immerseus'Corruption level. At the start of each Split Phase, one hostile add willspawn for every 4 points of Corruption, and one friendly add will spawn foreach 4 points of Corruption that has been removed. For example, when Immerseusenters the Split Phase with 76 Corruption, there will be 19 hostile adds and6 friendly adds. The upshot of this is that, as the fight progresses, therewill be more and more healing adds, and fewer and fewer hostile adds.

There appears to be a minimum number for each type of add, meaning thateven the first first Split Phase contains a few friendly adds (in addition tothe large number of hostile ones). Likewise, even if you enter the lastSplit Phase with Immerseus being extremely low on Corruption, there will stillbe a handful of hostile adds.

6. Immerseus Phase↑top

During the Immerseus Phase, the boss is stationary in the center of hisroom, and he must be tanked. This phase ends when Immerseus' health reaches0%. During the Immerseus Phase, the boss uses a number of abilities againstyour raid, which we will go over before discussing the strategy for thisphase.

6.1. Abilities

During this phase, Immerseus uses several abilities against yourraid.

• Sha Bolt is an ability that Immerseus uses roughly every 10 seconds.It deals moderate Shadow damage to every raid member (and to anyone within 5yards of them), and places a small void zone at their location. These voidzones persist until the end of the phase. When the phase ends, the void zoneswill move towards Immerseus and disappear upon reaching him.
• Swirl is an ability that has two components. Immerseus willsummon a number of small void zones that move around the room, dealing damageto any players who come in contact with them, and knocking these players up inthe air. Immediately afterwards, Immerseus will channel a very damaging jet ofwater in front of him, and he will spin clockwise for 10 seconds. After the 10seconds are up, the void zones will disappear and Immerseus will resume hisusual behaviour.
• Corrosive Blast is a frontal cone attack that deals Shadow damageto affected players, and debuffs them to take 300% increased Shadow damage for45 seconds. This effect stacks. Immerseus casts this ability every 35 secondsor so. This ability requires a tank switch.
• Seeping Sha is essentially a protective barrier that surroundsImmerseus (displayed as a ring of water). Players who get too close to the bossand enter this water take damage and are knocked back. This prevents playersfrom walking through the boss, but since his hitbox is very large, it does notinterfere with melee players' ability to attack.

6.2. Strategy

Your raid's strategy during this phase is quite simple. We will summariseit before going into more details.

• Tank Immerseus facing away from raid members, and perform a tank switchafter each Corrosive Blast.
• Have the entire raid spread out around the boss. Players should stayspread out at least 5 yards apart, and should always move out of the voidzones caused by Sha Bolt as soon as they appear.
• When Immerseus casts Swirl, make sure to avoid coming in contactwith the small moving void zones. You also must make sure to avoid being hitby the jet of water that Immerseus shoots, something which may require you tomove extensively depending on where you are located.
• Stay out of the center of the arena, since being here damages and knocksyou back.

6.2.1. Positioning

The positioning of the raid is arguably the most important aspect of thisphase. To begin with, no one except the tank currently tanking Immerseus shouldbe located in front of him. The other tank should be close to this area inorder to be able to move into position when they need to taunt (remember thatyou cannot run through Immerseus, only around him).

The raid must be spread out evenly around Immerseus for several reasons.First of all, this is important because over the course of the phase, therewill be a very large number of Sha Bolt void zones accumulating, soyou will need to make use of most of the room. Secondly, it is important tohave raid members spread out at least 5-yards apart in order to avoid takingany additional damage from the nuking component of Sha Bolt. Finally, duringthe Split Phase, your raid will have to kill and heal adds that spawn frommany positions all around the room, so it is important that raid members bealready in place to deal with these adds.

It is also worth emphasizing that you will have to distribute your healersaround the room in such a way that each group of players is in range ofsufficient healers.

6.2.2. Handling the Abilities

Handling Sha Bolt is, by and large, handled simply by correctpositioning. That said, each player will need to move regularly throughout thephase, each time a new void zone appears at their feet. Ideally, players shouldmove only slightly outside the void zone, so that the next void zone is placedright next to it, meaning that no free space is wasted (by ending up surroundedby void zones).

Moreover, players should form such a pattern so as not to be trapped between void zones on all sides, for two reasons. Firstly, in order to avoidImmerseus' Swirl ability, you must have freedom of movement. Secondly,at the end of each Immerseus Phase, all these void zones move to the center ofthe arena, and you should not be in their way when they do so.

Handling Swirl itself is not something that can be planned extensivelyahead of time, since the pattern of the moving void zones is not easilypredictable. Players will just have to have reasonable positional awarenessand to move accordingly. As for avoiding the jet of water, this simply requiresthat players pay attention to the facing of the boss, and move ahead of time ifthe jet is heading their way.

Finally, players have to stay out of Immerseus' melee range (or rather,more accurately, outside of the boss' model) in order to avoid taking damagefrom Seeping Sha.

7. Split Phase↑top

Whenever Immerseus reaches 0% health, he splits up into a number of smalladds, a combination of friendly and hostile adds, as weexplained above. The phase ends when all the adds have been accountedfor (having been healed or killed, respectively, or having reachedImmerseus).

7.1. Abilities

The friendly adds, which must be healed, are calledContaminated Puddles. The hostile adds, which must be killed, are calledSha Puddles. These adds do not do anything other than move towards thecenter of the room. The hostile adds do not melee, nor do they need to betanked. They can, however, be stunned and rooted.

During this phase, you will be confronted with several mechanics.

Each time a Sha Puddle or a Contaminated Puddle reachesImmerseus, it will cause the raid to take a moderate amount of Shadow damage.Each time a Purified Puddle (a fully healed Contaminated Puddle) reaches theboss, the raid will suffer a small amount of Frost damage. To clarify,Contaminated Puddles that are fully healed do not disappear, and they continueto move towards the boss.

When a Sha Puddle is killed, all players within 10 yards of its locationgain a 25% increase in damage done to Sha Puddles for a short time. Thiseffect stacks.

When a Contaminated Puddle is fully healed, all players within 12 yardsgain 25% of their mana, and gain a 75% increase in healing done for a shorttime. This effect stacks. It is also worth noting that Contaminated Puddlesmove slower the more health they have.

Finally, Seeping Sha continues to function during this phase just asduring the Immerseus Phase.

7.2. Strategy

The strategy for this phase is not complicated. All raid members shouldheal or damage the hostile adds that are in range of them (remember, your raidshould be spread out evenly around the room so that all the adds can bereached). Healers will have to pay attention to the damage that the raid willtake each time an add reaches the center of the room.

The most important thing to do in order to maximise your raid's performanceduring this phase is to make sure that DPS players are within 10 yards ofdying Sha Puddles whenever possible, and that healers are within 12 yardsof Contaminated Puddles that are being healed to full health, in orderto benefit from the buffs that are provided in this way.

8. When to Use Heroism/Bloodlust/Time Warp↑top

We recommend using Heroism/ Bloodlust/ Time Warp at thestart of the fight. This is mostly because there is no specific reason to useit at a later time, and benefiting from all raid members having all theircooldowns available at the start is very advantageous. Additionally, thistiming is suitable since the first Immerseus Phase is the longest of the fight,and you should try to get it out of the way as quickly as possible. GivenImmerseus' low health, if you use Heroism/Bloodlust/Time Warp in any of thesubsequent Immerseus Phases, you may well end up having the boss die beforeyour cooldown runs out, having the rest of it go to waste while the Split Phaseis starting.

9. Summing Things Up↑top

In this section, we will very briefly summarise what the players belonging toeach of the three roles have to do during this fight.

9.1. Tanks

• Tank Immerseus facing away from other raid members, and perform atank switch (in order to handle the Corrosive Blast ability).

9.2. Healers

• Beware of the unavoidable raid-wide damage from Sha Bolt (ImmerseusPhases only).
• Heal Contaminated Puddles, and be within 12 yards of them when theyreach full health.
• Beware of the unavoidable raid-wide damage that goes out each time anadd reaches the center of the room (Split Phase only).

9.3. DPS

• DPS Immerseus.
• DPS Sha Puddles, and be within 10 yards of them when they die.

9.4. Everyone

• Avoid standing in the void zones created by Sha Bolt (ImmerseusPhase only).
• Beware of Swirl; do not be in front of Immerseus, and avoid themoving void zones.
• Do not enter Immerseus' hitbox.

10. Heroic Mode↑top

The Heroic mode of the Immerseus encounter is possibly the mostaccessible Heroic mode in the Siege of Orgrimmar, and it presents few changesfrom the Normal mode version.

10.1. Differences From Normal Mode

Aside from the usual increased health and damage associated with all Heroicmodes, there are two key differences in the mechanics of the fight, one in eachphase.

10.1.1. Immerseus Phase

Once per Immerseus Phase, the boss gains a buff called Swelling Corruption (the boss will cast this spell more than once ifyou spend enough time in the phase, but the cooldown is so high that this isunlikely to ever happen). Swelling Corruption has an unlimited duration, andit has a certain number of stacks. Specifically, the buff has one stack forevery 2 points of Corruption that the boss has. This means that the very firstSwelling Corruption has 50 stacks, and then each one has fewer and fewerstacks as the fight goes on.

Every attack made against the boss removes a stack of the buff, and causesthe attacker to gain a stack of a dispellable 6-second Shadow-damage DoT, and to spawnan add called Congealed Sha. The DoT's damage increases over the courseof its 6-second duration, and the Congealed Sha adds do not do anything exceptmelee their main aggro target. Swelling Corruption has no other effects, andonce all of its stacks are gone, it disappears.

10.1.2. Split Phase

During the Split Phase, Immerseus gains an ability called Sha Pool.This causes the center of the room (the area where your raid cannot go withoutbeing damaged and knocked back, and the same area where all the adds converge)to become a large void zone. Any players standing inside the void zone takea small amount of Shadow damage every second. The void zone grows slowly overthe course of the Split Phase, and it also grows each time a Sha Puddle,Contaminated Puddle or Purified Puddle reaches it. As it increases in size,its damage is also increased. The void zone shrinks in size whenever itdamages a raid member, and it disappears as soon as the phase ends.

10.2. Strategy

The overall strategy for the fight remains unchanged. All that your raidmust do is react appropriately to the two new abilities.

10.2.1. Immerseus Phase

When Swelling Corruption is cast, the resulting Congealed Shasmust be killed as quickly as possible. While they are not very damaging, thereare so many of them that you must have a tank pick them up so that they do notoverwhelm the raid. There are two things worth mentioning here.

First of all, we advise 10-man raids to deal with the debuff in twostages. DPS players and tanks should make enough attacks to reach 2-3 stacksof the debuff (but not more than this, since the DoT damage would be veryhigh), and then wait (stopping DPS) for the adds to spawn. After handling theadds, when players' health has stabilised, a second round of attacks can bemade, which should clear all of the remaining stacks of Swelling Corruption.After the very first Swelling Corruption of the fight, when the number ofstacks is highest, it is no longer necessary to do this, and it is possibleto simply attack the boss normally and then deal with the resulting adds.

Given the much higher number of players in 25-man raids, it is possibleto simply attack Immerseus normally even during the first Swelling Corruptionof the fight.

Note that it is possible to dispel the DoT, something which can be usefulin increasing the number of Swelling Corruption stacks your raid can take downin a single wave.

Second of all, you will need to come up with a means of grouping most or allof the adds up so that they can be killed more easily. The best way to do thisis to have a Holy Paladin turn on Righteous Fury, and have a tankstanding by near them. The threat generated by the Paladin's heals will drawall the adds to them, and the tank can them pick them up as soon as they arethere. If you do not have access to a Holy Paladin, you will need to lookfor other methods offered by your raid's composition.

10.2.2. Split Phase

The easiest way to handle the Sha Pool void zone is to have raidmembers with defensive cooldowns step into the void zone for a short time, atregular intervals during the Split Phase. This prevents the void zone fromgrowing too much. The damage that it deals to players is quite low, so as longas healers are prepared for it, it should not cause problems.

Other than this, simply perform the Normal mode strategy for this phase.

11. Learning the Fight↑top

There are two crucial aspects that your raid must master in order todefeat this boss.

The first is proper positioning during the Immerseus Phases,allowing you to avoid taking any damage from Sha Bolt void zones andallowing all the adds during the Split Phase to be handled quickly andefficiently.

The second is maximising the benefits from the buffs that go out in a smallradius around adds that are dying or being healed to full during the SplitPhase. Having many raid members benefiting from the damage and healing buffscan make these phases go by much more smoothly.

12. Concluding Remarks↑top

This concludes our raid guide for Immerseus. We hope you havefound it helpful. Please do not hesitate to post any feedback you may have onour forums.

13. Changelog↑top

• 24 Nov. 2013: Improved the Heroic mode strategy suggestions.
• 25 Sep. 2013: Added Heroic mode strategy.
• 15 Sep. 2013: Added a link to the video guide.
• 13 Sep. 2013: Made several updates after doing the fight on liverealms.
  • Updated 10-man health values, and added 25-man health values.
  • Added a mention that we believe the enrage timer to be about 10minutes.
  • Added that we believe there is a minimum number of each add type that mustbe active in each Split Phase, which explains why even the first Split Phasecontains a few friendly adds (previously, the guide was simply stating thatwe do not know).
  • Added a mention that using Heroism/ Bloodlust/ Time Warpin the first Immerseus Phase is important because if used in any otherImmerseus phases, the cooldown would probably last longer than the phaseitself.
• 29 Aug. 2013: Added Summarising Things Up section.