Baron Geddon, Doom-Bringer: how to beat

ReferenceBuilt from the game’s data

Raid “Molten Core”, boss 5 of 9 · level 60. Abilities and damage, turn-by-turn rhythm, phases, what the tank, healer and damage dealers do.

Boss 5 of 9 · level 60 · raid Molten Core. Everything on this page comes from the game’s own data: when the boss changes, so does the guide.

In short

Mostly hits the tank: the hardest hit is “Umbral Bolt”. No whole-party hit.
The tank loses 31% of their Health per turn on average (heroic 37%), the others are barely touched: heal the tank every turn.
Boss Health: phases at 66% and 33% — keep big cards for the end.
Wounds (“Ignite Mana”) are removed by a cleanse.
Taunt before boss turns 1, 4, 7…

Tactics

Step by step — what each role does: the pull, the party-wide hit turns, Taunt’s rest, phases and enrage.

When	Tank	Healer	Damage dealers
1. Pull · turn 1	Taunt before the first enemy turn: it holds the boss for 2 turns. Keep a defensive card for “Umbral Bolt”.	Heal the tank from turn one: they lose 31% (heroic 37%) of their Health per turn on average, but never more than 2,383 per turn.	Steady damage on the boss — no burst while the tank builds threat.
2. Turns 3, 6… · Taunt rests	The stance holds (−40% damage): hit the boss — your damage makes 3× threat. Next turn — Taunt again.	As usual: heal the tank.	No burst — don’t out-threat the tank, or the boss turns on you.
3. Wounds and debuffs: “Ignite Mana”	Keep your Health above half — a wound ticks every turn.	Cleanse as soon as it lands; no cleanse — heal with a margin.	Damage on the boss: wounds are the healer’s job.
4. Boss shield and heals: “Barrier of Light”, “Gift of Light” and “Renew”	Keep Taunt on rhythm — nothing changes.	As usual.	The boss’s shield soaks damage first — play big cards when it is down; steady damage every turn.
5. Phase change: 66% and 33% of the boss’s Health	Reach the threshold at full Health with Taunt ready.	Top the party to full Health before the threshold — a new phase brings new moves.	Party hurt — hold damage at the threshold until the healer catches up.

How much reaches a hero

To the tank (Health ~2,650): up to 2,118 per hit and up to 2,383 per whole boss turn; on heroic — up to 2,383 and up to 2,515.
To everyone else (Health ~1,300–1,500): up to 885 per hit and up to 1,125 per turn; on heroic — up to 1,200 and up to 1,350.
A card can read more than a hero’s whole Health — that is not a mistake: the card is strong, but a hero never takes more than the cap per hit. A shield takes the hit first and is used up in full; past the shield, no more than the cap reaches Health.
The numbers are for a level 60 hero in PvE gear; your Health differs — the cap follows it: per hit 80% / 90% of the tank’s Health and 59% / 80% of anyone else’s, per turn — 90% / 95% and 75% / 90% (normal / heroic).

Abilities

“To a hero” is the most that reaches a level 60 hero’s Health (hit cap applied, before Hardiness); “/” separates normal and heroic. “On the card” is what the boss card reads: it can be more than a hero’s whole Health, and that is not a mistake — the card is strong, but no more than the cap lands per hit. Bold — the most dangerous. More — How to read the guide.

Ability	What it does	On whom	To a hero (normal / heroic)	On the card	First turn	Cooldown	Lasts	Removed	When
Onslaught	Boss power: hits the target	target — usually the tank	up to 1,400 / 1,764 per hit	1,400 / 1,764	—	every other turn; may finish a wounded target off-beat	—	—	whole fight
Ignite Mana	Wound: damage every turn	target — usually the tank	up to 2,068 / 2,515 per turn	2,068 / 2,606	—	at most once per 5 turns	3 turns	by cleanse	whole fight
Umbral Bolt	Hits the target	target — usually the tank	up to 2,118 / 2,383 per hit	5,514 / 6,948	—	whenever it has crystals	—	—	whole fight
Unstable Sigil	Discards cards from hand	target — usually the tank	—	—	—	whenever it has crystals	—	—	whole fight
Barrier of Light	Shields itself	the boss itself	—	—	—	whenever it has crystals	—	—	whole fight
Gift of Light	Heals itself	the boss itself	—	—	—	whenever it has crystals	—	—	whole fight
Renew	Heals itself	the boss itself	—	—	—	whenever it has crystals	—	—	whole fight

Why the card reads more

Ignite Mana. The card reads 2,068 / 2,606 per turn, but over a whole enemy turn the tank loses at most 90% / 95% of their Health — up to 2,068 / 2,515.
Umbral Bolt. A strong card — it reads 5,514 / 6,948, but the tank never takes more than 2,118 / 2,383 per hit (the cap is 80% / 90% of their Health); a shield is used up in full first. On any other hero — up to 885 / 1,200.

Turn-by-turn rhythm

A boss turn is the enemy turn after yours; the party moves first. The boss’s Onslaught hits the target every other turn, its cards whenever it has crystals (each has its own cooldown — see the table above). Here is what follows a strict turn order.

Boss turn	What happens
1	Tank presses Taunt before this turn — it holds turns 1–2
2	Regular turn: hits on the tank
3	Taunt is resting: the stance (−40% damage) keeps the boss on the tank — damage dealers, no burst
4	Tank presses Taunt before this turn — it holds turns 4–5 · Without healing the tank falls on this turn
5	Regular turn: hits on the tank
6	Taunt is resting: the stance (−40% damage) keeps the boss on the tank — damage dealers, no burst
7	Tank presses Taunt before this turn — it holds turns 7–8

Phases and enrage

From 66% Health — phase 2: the deck is reshuffled, same moves.
From 33% Health — phase 3: the deck is reshuffled, same moves.

Roles

Tank: tanking and when to taunt

Taunt before boss turns 1, 4, 7…: it holds the boss for 2 turns, then the button rests for 1 turn — the stance (−40% damage) still holds then.
You lose 31% of your Health per boss turn on average, up to 90% on a heavy turn; on heroic — 37% and up to 95%.
Keep defensive cards for “Umbral Bolt” — it is the hardest hit on you.
Without healing you would fall on boss turn 4.

Healer: when to heal

Main healing goes on the tank every turn: they lose 31% of their Health per boss turn on average (heroic 37%).
No whole-party hit, and the boss barely touches the others — nearly all healing goes to the tank.
“Ignite Mana” — a wound on the target: up to 2,068 (heroic — up to 2,515) per turn for 3 turns; a cleanse removes it, it comes back no sooner than 5 turns later.
The others survive all 10 turns of the test without healing — all healing can go to the tank and after party-wide hits.

Damage dealers: what to hit and when

Boss Health — 121,275 (heroic 121,275).
The boss shields itself (“Barrier of Light”) — the shield soaks damage first; play your big cards when it is down.
The boss heals itself (“Gift of Light” and “Renew”) — steady damage every turn beats rare big hits.
Before 66% and 33% of the boss’s Health, hold damage if the party is hurt: a new phase brings new moves.
Don’t outpace the tank’s threat on Taunt’s rest turn (boss turns 3, 6, 9…): the tank’s damage makes 3× threat, but a burst can still pull the boss.

Danger points

The hardest hit on the target is “Umbral Bolt”. The card reads 5,514 (heroic 6,948), but the tank takes at most 2,118 (heroic 2,383) per hit, anyone else 885 (heroic 1,200); a whole boss turn — at most 2,383 (heroic 2,515) to the tank and 1,125 (heroic 1,350) to the others. Nobody at full Health falls in a single turn.
“Unstable Sigil”: discards cards from hand.
Phase change at 66% and 33% Health — a new deck; enter it with the party at full Health.
Without healing the tank falls as early as boss turn 4 — the healer must not skip a single turn.

Average damage

Measured by the game engine: a level 60 party in PvE gear, the tank holds Taunt, nobody else does anything — 10 turns of the boss. Percentages are the share of Health one boss turn takes: that is what needs healing.

Mode	Tank: per turn	Tank: heavy turn	Others: per turn	Others: heavy turn	Without healing would fall on boss turn
Normal	31%	90%	0%	0%	tank — turn 4, healer — alive, fighter — alive
Heroic	37%	95%	0%	0%	tank — turn 4, healer — alive, fighter — alive

Party and gear

Party: 5 heroes — tank, healer, 3 damage dealers.
Recommended item level: 220, on heroic — 232. It is advice only: enemies don’t change.
Heroic: boss damage ×1.26, Health ×1 over normal.
The guide’s numbers are for a party of “one player + level 60 residents”; with another line-up the boss’s strength differs a little — the game fits it to the party.

Loot

All of the boss’s loot with rough drop chances is in the item atlas; rules and items by boss are on the Molten Core page.

Previous boss — Garr, Lord of Embers. Next boss — Shazzrah, the Flame Whisperer.

All bosses of the place — Molten Core. Party combat rules — How to beat: level 60 bosses.