The Twin Fangs — Guide to a boss of The Venomous Abyss

Single-phase two-target cleave fight: Vexhul (green) and Ithraz (red), with separate health pools. No mechanic is complex on its own, but they are dense and they overlap.

The main mechanic is Eternal Venom, a stacking DoT gained every time you take poison damage. This fight has a great many sources of poison damage. On reaching the threshold the player dies instantly: nine stacks on Mythic, ten on Heroic. On Mythic anyone who dies with stacks spawns globules that redistribute them across the living, so one death triggers more. The only way to shed stacks is being bitten by Ithraz during Ravenous Feast, a three-bite soak: anyone who takes one bite cannot take a second, so three separate groups are needed, one per bite.

Each serpent brings its own block of mechanics. Vexhul spawns acid globules that must be soaked before they burst on their own, on Mythic protected by a shield that only breaks to stuns, and calls adds from the sea that need killing immediately. Ithraz drives the soaks, slams the platform in a numbered sequence handled by the tanks, and on Mythic summons adds requiring 14 interrupts spread across the raid.

On top of any enrage timer the fight has a spatial limit. Every time the two serpents submerge and reposition they leave behind a permanent venom slick, and after three submerges the triangular platform is exhausted. That's the constraint you hit first, so in practice the DPS check is closing within three submerges.

TL;DR

What to do

Everyone

Always: watch your own Eternal Venom stacks.
Always: soak the Caustic Globules before they burst on their own.
Every Ravenous Feast: three separate groups cover the three bites, one each.
Every Ravenous Feast: a dedicated group absorbs the Tainted Blood founts.
Every Submerge: move in the direction of the Vile Flood beam, to cover the shortest distance.
With Coiling Ichor: drop pools at the edge.

Tank

Stone Breaker: cover the impacts in the numbered order of the circles. The two tanks can alternate.
Tank swap on Caustic Deluge and, on Mythic, Blood Torrent.

Healer

Always: Toxic Fumes deals damage every 2 seconds for the entire fight.
Every Ravenous Feast: Tainted Blood founts absorb healing within 5 yards.
In Noxious Slicks: anyone standing in them takes +30% damage.

DPS

Always: break the Barbed Bulwarks on the globules with stuns, ideally AoE ones.
Always: kill the Spawn of Vexhul immediately.
Every Rouse the Brood: cover the 14 interrupts, split between right, left and center.
End of fight: bring Vexhul and Ithraz to matching percentages.

What can kill you

Ability	When	How to avoid it
Eternal Venom threshold (9 on Mythic, 10 on Heroic)	Cumulative	Avoid poison damage and use Ravenous Feast to shed stacks
Feasted	Ravenous Feast	+800% damage taken: never two consecutive bites on the same person
Caustic Globule	After Caustic Deluge	Touching one alone unintentionally
Stir the Depths	Base cycle	The waves apply Eternal Venom
Corrosive Spit	With spawns alive	Frontal line that applies another stack
Noxious Slick	After each Submerge	Constant damage plus +30% damage taken
Vile Flood	After each Submerge	14-second frontal torrent during repositioning

What wipes the raid

Mistake	When	Consequence
A player dies with stacks	Always, Mythic	Spawns extra Caustic Globules that redistribute stacks across the raid
Missed interrupts	Rouse the Brood	Visceral Burst: stacking raid damage
A Tainted Blood fount not absorbed	Ravenous Feast	Tainted Burst: huge raid damage
A Stone Breaker impact hits nobody	Stone Breaker	Damage on everyone, ignoring armor
Globules left to burst	Always	One Eternal Venom stack on the whole raid
One serpent killed too early	End of fight	Uncoiled Wrath: +30% damage every 4 seconds to the survivor
Reaching a fourth Submerge	Spatial enrage	No platform left to stand on

Timeline

Point	What happens
Cycle	Caustic Deluge and globules (Vexhul) · Ravenous Feast and Tainted Blood (Ithraz) · Stone Breaker · Rouse the Brood · Coiling Ichor · Venomous Emergence · Stir the Depths
Every ~2 minutes (100 energy)	Submerge: both dive and reposition, leaving a permanent Noxious Slick. Then Vile Flood and Sanguine Storm simultaneously
After the 3rd Submerge	The triangular platform is exhausted

The real DPS check is closing the fight within three Submerges.

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Detail

Eternal Venom

Eternal Venom deals periodic damage and is cumulative. On reaching the threshold the player dies instantly: 9 applications on Mythic, 10 on Heroic.

Unavoidable sources: Venomous Emergence, which applies a stack to the whole raid, and Caustic Globules that burst without being soaked.

Avoidable sources: the waves from Stir the Depths, Corrosive Spit, the splashes from Caustic Deluge, and Vile Flood.

The only way to lose stacks is Ravenous Feast. There is no dispel and no decay.

On Mythic, a player who dies with stacks spawns extra Caustic Globules: their stacks redistribute across the living, which is how the fight turns from controlled to a wipe within seconds.

Vexhul — green serpent

Caustic Deluge — a 5-second channel on the tank that ejects acid splashes. Each splash deals damage and applies Eternal Venom within 4 yards, and forms a Caustic Globule. Envenomed grants +10% Caustic Deluge damage taken per stack: tank swap.
Venomous Emergence — damage and a stack on the whole raid, then the Spawn of Vexhul appear, three at a time in PTR testing. They cast Corrosive Spit, a frontal line applying another stack. Priority kill.
Stir the Depths — 6 seconds of constant damage plus waves crossing the platform and applying Eternal Venom. They rarely come alone: in testing they appeared during soaks and repositioning.

The Caustic Globules break after 10 seconds.

Situation	Effect
The globule bursts on its own	Damage plus Eternal Venom on the whole raid
A player touches it	Damage plus Eternal Venom on that player only

On Mythic they are protected by the Barbed Bulwark: blood expelled by Ithraz via Blood Torrent congeals around each globule, forming a barrier that deals damage and knocks players back. It is destroyed by interrupting it. In PTR testing stuns worked while grips and knockbacks did not. Given the spawn positions, a wide AoE stun is far more efficient than scattered single stuns.

Ithraz — red serpent

Ravenous Feast — attempts to devour players three times in a row. Each bite deals damage split among players within 14 yards, consumes 1 Eternal Venom stack from those struck, applies Feasted and knocks them back.

Feasted, for 8 seconds, increases Ravenous Feast damage taken by 800% and prevents Ithraz from consuming further stacks from that player. A second bite is therefore doubly pointless. In PTR testing the values on subsequent bites were on the order of 800% and 2400% additional damage.

Setup: three assigned groups, one right, one left, one center. Each group covers one bite and then clears out.

Tainted Blood (Mythic) — alongside this, Ravenous Feast expels several blood founts for up to 8 seconds, each absorbing healing from players within 5 yards. If a fount isn't fully absorbed before expiring, Tainted Burst deals huge raid damage. A dedicated group is needed in parallel with the bite soaks.

Stone Breaker — Ithraz roars pushing everyone back, then repeatedly slams the platform. Each impact deals damage within 3.5 yards and grants +33% Stone Breaker damage taken per stack for 1.5 minutes. If an impact hits nobody, the damage goes to the whole raid with knockback, ignoring armor.

The circles appear numbered on the ground and must be covered in sequence. It's a tank job, since only tanks can hold the stacks, and they can alternate.

Coiling Ichor — increasing damage in a shrinking area. On expiry it forms a Congealed Gore pool lasting 2 minutes and slowing by 50%. Pools go at the edge: space is already the fight's scarce resource.

Rouse the Brood (Mythic) — summons several Broodlings of Ithraz and releases a blood nova on the raid. Each broodling casts Visceral Burst: raid damage plus a stacking DoT. If the cast is interrupted, the broodling retreats.

In PTR testing there were 14 interrupts, spread across three zones: left, between the two bosses, and right. The raid is split accordingly. Four Protection Paladins were brought in testing specifically for this mechanic: not a live comp, but it shows how much the available interrupt count matters.

Submerge and repositioning

Roughly every 2 minutes both serpents dive and reposition.

Submerge floods the surrounding area with venom, forming a Noxious Slick: constant damage and +30% damage taken. That portion of the platform is lost.

Pull        → fight at point 1
1st Submerge → point 1 lost, move to point 2
2nd Submerge → point 2 lost, move to point 3
3rd Submerge → point 3 lost, there is no point 4

Then they attack together:

Vexhul, Vile Flood — moves to the center and channels a frontal torrent for 14 seconds, applying Eternal Venom to anything it touches.
Ithraz, Sanguine Storm — moves to the opposite side and bombards the platform for 18 seconds, each glob dealing damage within 4 yards and leaving a Congealed Gore pool on Heroic and Mythic.

You must move in the direction of the beam: going the other way means crossing the full arc and eating the Sanguine Storm along the way.

Background damage and kill order

Toxic Fumes — raid damage every 2 seconds.
Blood Torrent (Mythic) — on a tank: a cumulative healing absorb every second for 5 seconds.
Concentrated Spittle and Clotted Bolt — the serpents attack their target at range if out of reach.

The two serpents have separate health pools. Uncoiled Wrath: when one dies, the survivor gains +30% damage every 4 seconds, cumulative. They must be brought to similar percentages and killed almost simultaneously.