Primordius Detailed Strategy Guide (Heroic Mode included)
Table of Contents

Introduction
This guide is intended to provide a comprehensive description of the encounter with Primordius in Throne of Thunder. It is targeted at anyone who desires to understand the fight mechanics.
This guide is updated for World of Warcraft WoD 6.1.2.
Primordius is the eighth boss in the Throne of Thunder. This is not a complicated boss, despite the very large number of abilities present in the encounter.
The fight will mostly put a strain on your DPS players, who must manage several buffs and debuffs in order to meet the DPS requirement for defeating Primordius before he enrages.
General Information
Health Values
Difficulty | Primordius | Living Fluid | Viscous Horror |
---|---|---|---|
10-man | 218M | 800K | Heroic-only |
10-man Heroic | 305M | 1.2M | 8.8M |
25-man | 654M | 2.4M | Heroic-only |
25-man Heroic | 916M | 3.5M | 17.4M |
LFR | 654M | ??M | Heroic-only |
Enrage Timer
Primordius has a hard enrage timer of 8 minutes, after which he buffs himself with Berserk, dealing greatly increased damage, and wiping the entire raid in a matter of about 10 seconds. There is a soft enrage timer that causes Primordius' damage done to increase progressively throughout the fight. If your raid fails to execute the strategy properly, the damage increase will be sped up.
Raid Composition
Difficulty | Tanks | Healers | DPS |
---|---|---|---|
10-man | 2 | 2-3 | 5-6 |
10-man Heroic | 2 | 2-3 | 5-6 |
25-man | 2 | 5-7 | 16-18 |
25-man Heroic | 2 | 5-7 | 16-18 |
Loot
Armor
Item Name | Armor | Slot | Main Stats |
---|---|---|---|
![]() |
Cloth | Chest | Intellect |
![]() |
Cloth | Wrists | Intellect |
![]() |
Cloth | Hands | Intellect/Spirit |
![]() |
Leather | Legs | Intellect |
![]() |
Cloth | Legs | Intellect/Spirit |
![]() |
Leather | Hands | Agility |
![]() |
Head | Intellect | |
![]() |
Wrists | Agility | |
![]() |
Hands | Agility | |
![]() |
Plate | Shoulders | Intellect |
![]() |
Plate | Wrists | Intellect |
![]() |
Plate | Hands | Strength |
![]() |
Plate | Shoulders | Strength/Parry |
![]() |
Plate | Legs | Strength/Parry |
Weapons
Item Name | Type | Main Stats |
---|---|---|
![]() |
1H Mace | Strength/Parry |
![]() |
Shield | Strength/Dodge |
Cloaks, Rings, and Trinkets
Item Name | Type | Main Stats |
---|---|---|
![]() |
Trinket | Spirit/Shield on use |
![]() |
Trinket | Agility/Haste |
![]() |
Cloak | Strength |
![]() |
Ring | Strength |
![]() |
Trinket | Crit/Strength |
DPS Requirements
Assuming that, in 10-man, about 5 Living Fluids spawn every 10 seconds, and that you will kill about 2/3 of them (so 160 over the course of 8 minutes), and that tanks do half as much damage as DPS, the DPS requirements are as follows:
- 10-man with 5 DPS: 142k DPS;
- 10-man with 6 DPS: 122k DPS.
We will update this section as soon as we have health values for 25-man.
Note that most players will be benefiting from damage-increasing buffs for a good part of the fight.
Overview of the Fight
The encounter against Primordius is a rather straightforward single-phase fight. Despite the fact that there are very many abilities used throughout the fight, only a handful of them really matter.
By default, all players deal greatly reduced damage to Primordius. If this were the case for the entire fight, your raid would have no chance of defeating the boss before hitting his 8-minute enrage timer. Fortunately, there are two mechanics in place that allow you to deal additional damage.
- Adds will pour out of the sides of the room throughout the entire fight, and make their way to Primordius. When these adds are killed, they leave behind void zones that provide various buffs to raid members who stand in them (stacking increases in stats, haste, mastery, and critical strike chance).
- When a raid member reaches a combined total of 5 stacks of the
above-mentioned buffs, they become
Fully Mutated for 2 minutes, dealing full damage to Primordius for this time.
The difficulty and complexity of the encounter comes from the fact that if the adds we talked about above are not killed before they reach Primordius, they buff him. Over the course of the fight, Primordius will temporarily gain certain combinations of damaging abilities to use against your raid, thanks to a resource that he passively gains at a slow pace. He gains this resource much faster if the adds, which do not do anything other than slowly move towards him after they spawn, are allowed to reach him.
Moreover, raid members are punished for taking additional stacks of beneficial buffs once they are Fully Mutated. When doing so, these beneficial buffs turn into detrimental ones. This means that raid members must be careful.
We have prepared the following video preview of the fight against Primordius, based on the testing from the Public Test Realms. Once we can do the fight on live realms, we will also publish an up-to-date video guide. We strongly recommend watching the video in order to get a better visual idea of the fight.
Class-specific Advice
On our forums, we are maintaining threads with class-specific advice for each of the fights of Throne of Thunder. So, make sure to check them out, and if you have things to share, do not hesitate to contribute!
Class | Forum Threads |
---|---|
![]() |
|
![]() |
|
![]() |
|
![]() |
|
![]() |
|
![]() |
|
![]() |
|
![]() |
|
![]() |
|
![]() |
|
![]() |
Abilities
Primordius
Base Abilities
By default, Primordius only has two abilities, as well as a buff.
Primordial Strike is a frontal cone attack that deals a high amount of Physical damage. Primordius casts this every 20 seconds or so. It is something that tanks are meant to simply survive.
Malformed Blood is a stacking debuff that Primordius applies to the current target. It deals Nature damage every 3 seconds, but also causes the player to deal increased damage to Living Fluids (adds that spawn throughout the encounter). This ability imposes a tank switch.
Mutated Abomination is a buff that Primordius retains for the entire duration of the fight. It causes the boss to take greatly reduced damage from any players who are not
Fully Mutated.
Evolution and Temporary Abilities
Primordius has a resource bar, that tracks his mutation level. His mutation increases slowly over time, and he also gains a large amount of mutation whenever one of the Living Fluid adds reaches him.
Whenever the mutation bar reaches maximum capacity (60), the boss permanently
gains a stack of a buff called Evolution, which increases his damage done by 10%, and his mutation is reset to 0. Each time the boss gains a new stack of
Evolution, he also gains one of the following abilities, at random.
Ventral Sacs is a raid-wide AoE damaging ability that deals Nature damage every second.
Caustic Gas is an ability that causes Primordius to deal a very large amount of Nature damage, split between all players within 25 yards of the boss.
Acidic Spines are nukes that Primordius targets random raid members with. They deal damage to all players within 5 yards of the target.
Volatile Pathogen causes Primordius to apply a debuff called
Pathogen Glands on random raid members. It deals a large amount of Nature damage every second to that player, for 10 seconds.
Metabolic Boost is a buff that increases Primordius' attack speed by 50%, and reduces the cooldown of his other abilities by 50%.
Erupting Pustules is an ability that causes Primordius to throw several projectiles that deal Nature damage in random areas of the room.
Primordius can not have more than 3 of these abilities active at one time. At the start of the fight, he will have none. After gaining the first Evolution stack, he will gain one ability, then another with the second Evolution stack, and then finally a third. The fourth time he is due to receive one of these abilities (on gaining the fourth Evolution stack), the ability replaces the first one that he received, and so on.
Living Fluids and Player Buffs
For the entire duration of the fight, Living Fluid adds will be pouring out from the edges of Primordius' room. They do not do anything other than head straight for the boss. They have very low health and they cannot be stunned or slowed.
When a Living Fluid reaches Primordius, the boss gains a certain amount of mutation, pushing him closer to the next level of Evolution.
When a Living Fluid is killed, it leaves behind one of two void zones.
Mutagenic Pools are small void zones that provide beneficial buffs to players who come in contact with them. In most cases, this is the void zone that a Living Fluid will leave behind.
Volatile Pools are large damaging void zones that move slowly towards Primordius, buffing him if they reach him. These void zones appear much less frequently than Mutagenic Pools.
Mutagenic Pools
When a player comes in contact with a Mutagenic Pool, they gain a stack
of one of the following buffs (at random). All of these buffs last 2
minutes.
Thick Bones grants a 5% increase in all stats.
Clear Mind grants a 10% increase in Mastery.
Improved Synapses grants 10% increase in Haste.
Keen Eyesight grants a 10% increase in Critical Strike chance.
When a player reaches a combined total of 5 stacks of these buffs, they
gain another 2-minute buff, called Fully Mutated, all the while retaining
their previous buffs. This transforms the
player's model into that of a Saurok. While Fully Mutated, players deal full
damage to Primordius. In addition to this, while Fully Mutated, any
Mutagenic Pools that players come in contact with no longer offer the
beneficial buffs listed above, but instead they apply a stack of one of the
following debuffs (at random). All of these debuffs last 5 minutes.
Fragile Bones reduces all stats by 10%.
Clouded Mind reduces Mastery by 20%.
Dulled Synapses reduces Haste by 20%.
Impaired Eyesight reduces Critical Strike chance by 20%.
Dispelling players is possible, but a single dispel will remove all mutations from that player.
Volatile Pools
If Primordius comes in contact with a Volatile Pool, he instantly
gains a new stack of Evolution, and he is healed for 10% of his maximum
health. If a player comes in contact with one of these void zones, they take a
large amount of damage and receive one of the debuffs mentioned above. The
Volatile Pools move very slowly towards Primordius' location.
Strategy
The strategy for this fight is extremely simple, and we will summarise it before going into more details.
- Have all DPS players who are not
Fully Mutated exclusively kill Living Fluids, and absorb the
Mutagenic Pools left behind in order to gain mutation stacks.
- Have all DPS players who are Fully Mutated exclusively DPS Primordius.
- Have your tanks face Primordius away from the raid, and alternate tanking
him, in order not to let the stacks of
Malformed Blood get too high. The tank who is not currently tanking Primordius should be attacking the Living Fluids, as Malformed Blood grants increased damage against these adds.
- Move Primordius away from any
Volatile Pools that are coming his way.
- Have the entire raid react to what ever 3 abilities Primordius is
empowered with.
Ventral Sacs requires the healers to heal a large amount of raid damage.
Caustic Gas requires multiple players to be within 25 yards of Primordius, to split the damage between them.
Acidic Spines requires players to spread out at least 5 yards apart.
Pathogen Glands requires the targeted random raid members to be healed intensely.
Erupting Pustules requires raid members to avoid the falling projectiles.
DPS Priority
While at first it may seem that DPSing Primordius and DPSing Living Fluids
are two tasks that achieve different goals, it is actually not so. Proper DPS
on the Living Fluids will only increase your ultimate DPS on Primordius. This
is because the only way to do significant damage to Primordius is to be
Fully Mutated (which in the process will also provide you with many
stacks of other beneficial buffs), and the only way to become Fully Mutated is
to come in contact with a lot of void zones left behind by dead Living
Fluids.
Therefore, anyone who is not Fully Mutated (and who, thus, would deal very low damage to Primordius) should be focusing entirely on killing Living Fluids. Anyone who is Fully Mutated should take advantage of this buff, and focus entirely on DPSing Primordius himself.
Assuming that the uptime on buffs is maximised (we talk about this below), doing this should ensure that there is enough DPS on Primordius to beat the enrage timer.
One final important note is that you should make sure to never kill
Living Fluids too close to Primordius, since you always risk them leaving
behind a Volatile Pool instead of a
Mutagenic Pool, which heals
Primordius for 10% of his health. If an add is too close to Primordius, you
should just let it reach him.
Managing Player Buffs
The buffs that you gain from coming in contact with Mutagenic Pools are
distributed randomly, so there is absolutely no reason to talk about the
specific benefits they offer. You have no way of controlling what these
buffs will be.
There are two important things to keep in mind regarding Mutagenic Pools. Firstly, when you come in contact with a pool and gain a buff, the pool disappears. Secondly, Mutagenic Pools disappear on their own if no one comes in contact with them for a long time.
Essentially, as you are progressing through the fight and killing Living Fluids, you must constantly be running over Mutagenic Pools to gain stacks of the beneficial buffs.
Unavoidably, some players will become Fully Mutated before others.
You should assign your highest DPS players to take the buffs first, so that
they get more time on the boss.
It is crucial to make sure that you do not come in contact with any other Mutagenic Pools once you are Fully Mutated, since doing so applies harmful debuffs to you that will greatly diminish your DPS potential.
We also do not recommend trying to "save up" Mutagenic Pools and then having many raid members transformed at once. This is a bad idea for several reasons, two of which being that you would be left with too few players on Living Fluids if everyone is Fully Mutated and attacking the boss, and also the fact that you run the risk of having the Mutagenic Pools despawn before you get to use them.
You should also never dispel players, because a single dispel will remove all buffs that the player has (both the beneficial and the detrimental ones). Players must simply be very careful not to touch any Mutagenic Pools once they are Fully Mutated.
Dealing with Boss Abilities
In addition to the tasks mentioned above (killing adds, picking up buffs, DPSing Primordius), you must also deal with his own abilities, in which ever combined form they are present.
At the start of the strategy section, we summarised how to deal with each ability on its own, and there is really not much more to be said about that. There are two combinations of abilities, however, that are quite problematic.
A combination of Gas Bladder and
Acidic Spines or
Gas Bladder and
Erupting Pustules requires
that your raid stacks within a 25-yard
radius of Primordius, but also that it spreads out. During a time like this
we advise stacking up tightly and using healing and defensive cooldowns to
survive. It may even be worth letting many Living Fluids reach Primordius
during this time, to force the next
Evolution faster, so that one of
the two contradictory abilities is removed.
When to Use Heroism/Bloodlust/Time Warp
We recommend using Heroism/
Bloodlust/
Time Warp at a point
in the fight where as many players as possible are
Fully Mutated, so that
you can do as much damage as possible to Primordius himself.
Learning the Fight
There are two very important aspects of the fight that your raid members must be familiar with.
First of all, everyone should understand how the gaining of buffs from
Mutagenic Pools works, and especially the drawbacks of coming in contact
with Mutagenic Pools once Fully Mutated. Players will have to become very
adept at moving into the Mutagenic Pools to gain buffs, and to avoid them
entirely when Fully Mutated.
Second of all, your raid will have to be quite focused in order to properly deal with Primordius' temporary abilities, all the while managing their own buffs. It is important to assign someone to call out over voice chat the basic idea of what the raid has to do depending on what abilities Primordius has (things like "stack" or "spread out").
Heroic Mode
The Heroic mode of the Primordius encounter is extremely similar to the Normal mode version. One difference in mechanics does exist, but its overall impact on the strategy is limited.
Differences From Normal Mode
In addition to the boss and the adds having increased health and dealing increased damage, a new add exists in Heroic mode. This add is called Viscous Horror, and a new one spawns every 30 seconds. The add requires a tank.
The Viscous Horror only has two abilities.
Deadly Mutagen causes the add to explode if it comes in close contact (about 10 yards) with Primordius, wiping the raid instantly.
Black Blood is a stacking debuff that the Viscous Horror applies on its tank. This deals damage to the target every 3 seconds, but also causes the target to deal additional Nature damage to Primordius with each one of their melee attacks.
Finally, Primordius can now have 4 mutations active at once, up from only 3 in Normal mode.
Strategy
The strategy for this fight remains quite similar to Normal mode. The only
significant difference is that one of the tanks will have to tank the
Viscous Horrors some distance away from Primordius, and that your raid
will have to kill them regularly. Every now and then, your tanks will have to
perform a tank switch (both because of Black Blood stacking on the
Viscous Horror tank, and because of
Malformed Blood stacking on the
Primordius tank).
Your DPS players should aim at going through 3 Fully Mutated
phases before the boss enrages after 8 minutes. The final Fully Mutated
period should be spent burning the boss while ignoring any remaining adds.
You should also try to have some players become Fully Transformed a bit before
others (for example, have the melee transformed a bit before the ranged) so
that you do not have the entire raid hunting for void zones to be
re-transformed at the same time.
Concluding Remarks
This concludes our raid guide for Primordius. We hope you have found it helpful. Please do not hesitate to post any feedback you may have on our forums.
Changelog
- 09 Jun. 2013: Added Heroic mode.
- 13 Mar. 2013: Added link to forum threads that contain class-specific advice for the encounter.
- 12 Mar. 2013: Several updates based on the live version of thefight.
- Updated health values in 10 and 25-man.
- Updated the guide to account for the fact that
Fully Mutated now happens at 5 stacks.
- Removed mentions of
Revival dispelling players, since this issue was remedied by a hotfix.
- 02 Mar. 2013: Added PTR video preview.
- MoP Classic Upgrade Packs Now Available in Battle.Net Shop
- Slightly Rising: Mythic+ Runs Per Week and Data Round-up for the Penultimate Week of The War Within Season 1
- Twitch Drop: Get Tock the Clocker Spaniel Pet
- Meet C.H.E.T.T.: Your New Key to Farming Valorstones in The War Within Season 2
- Time-Lost Proto-Drake Vanishes! A Painful Lesson for Dragon Hunters
- New Cataclysm Classic Valor Cap Set to Week 2 Due to Bug
- Patch 11.1 PTR Hotfixes: More Updates to Season 2 Dungeons & Mythic+ Tuning
- Season of Discovery Naxxramas Soft Reset Issue Fix and Warning