Assembly of Iron

The Assembly of Iron, known as the Iron Council during the PTR, is the fifth boss encounter in Ulduar found in The Assembly of Iron. The encounter consists of Steelbreaker, Runemaster Molgeim, and Stormcaller Brundir. Killing any one of the three will give a soft enrage of +25% damage to the other two and grant them additional abilities (similar to Fathom-Lord Karathress). Killing the second of the trio will grant the last with a final stage apart from their usual abilities which must be dealt with in different tactics.

The hard mode of this fight requires players to kill Steelbreaker last.

Abilities

 * Hard Enrage - 15 minutes after encounter starts.
 * [[Image:Spell Nature StormReach.png|32px]] Supercharge - as each boss dies, the others will gain a 25% damage increase and an additional ability. After the first Assembly member dies the remaining two will gain a 25% increase. When 2 Assembly members die the remaining will gain a 50% increase. Note that all abilities below do not factor the supercharge damage increase into their numbers.

Steelbreaker

 * 10 million hp on 25-man, 3 million hp on 10-man
 * Melee hits for: ~20k 25-man, ~10k 10-man.


 * [[Image:Ability GolemThunderClap.png|32px]] Fusion Punch - Inflicts 18,850 to 21,150 (25-man: 35,000) Nature damage to his target, and deals additional 15,000 (25-man: 20,000) Nature damage every 1 second, for 4 seconds. Hits tank only. The debuff is a magic effect and must be dispelled as quickly as possible.
 * [[Image:Spell Nature WispSplode.png|32px]] High Voltage - An aura that inflicts 1,500 (25-man: 3,000) to the whole raid every 3 seconds.
 * [[Image:Spell Nature LightningOverload.png|32px]] Static Disruption (1 dead) - Inflicts 3,500 (25-man: 7,000) Nature damage to enemies in 6 yards radius area. Also increases Nature damage taken by 75% for 20 seconds. Prefers ranged targets, but will choose a player in melee ranged if no ranged targets are available.
 * [[Image:Spell Shaman AncestralAwakening.png|32px]] Overwhelming Power (2 dead) - Targets the current tank on Steelbreaker. Causes the affected player to deal 200% more damage, but gain meltdown after the duration of the debuff. 60 second duration 10 man, 30 second duration heroic.
 * [[Image:Spell Nature LightningOverload.png|32px]] Meltdown  (2 dead) - Occurs at the completion of the Overwhelming Power debuff. Kills the tank and causes 29250 to 30750 Nature damage to any players within 15 yards. Divine Shield does not protect from it.
 * [[Image:Spell Nature LightningShield.png|32px]] Electrical Charge (2 Dead) - Any time a player dies after Steelbreaker is the only member of the Assembly alive Steelbreaker will heal for 20% of his maximum health and gain 25% extra damage (reducible by Wound Poison/Mortal Strike/Aimed Shot.)

Runemaster Molgeim

 * 10 million hp on heroic, 3 million hp on normal
 * Melee hits for: 8-10k against a well geared plate wearer on normal mode.


 * [[Image:Spell Arcane Arcane01.png|32px]] Rune of Power - A GTAoE that will buff anyone standing on this rune to do more damage. Summoned under one of the three assembly members who need to quickly be moved out of it's effect. 5 yd radius
 * [[Image:Spell Misc HellfirePVPCombatMorale.png|32px]] Shield of Runes - Shield absorbs up to 50,000 heroic 20,000 normal damage. If the shield absorbs the total amount this gives Moldeim a 50% damage increase for 15 seconds. Should be purged, dispelled or spellstolen.
 * [[Image:Spell Shadow AntiMagicShell.png|32px]] Rune of Death (1 dead) - 26 yard radius GTAoE which will do 3500 shadow damage per half second on heroic or 2750 Shadow damage per half second normal.
 * [[Image:Spell Shadow SealOfKings.png|32px]] Rune of Summoning (2 dead) - Creates a rune of summoning which periodically spawns Lightning Elementals. Elementals will charge toward members of the raid and explode on contact.
 * [[Image:Spell Nature LightningOverload.png|32px]] Lightning Blast (2 dead) - When the add reaches its target it will deal a 30 yard explosion of 14138 to 15862 Nature damage on heroic or 9425 to 10575 nature damage on normal killing the add in the process.

Stormcaller Brundir

 * 10 million hp on heroic, 3 million hp on normal
 * Melee hits for: 8-10k, crit for 25k against leather on normal mode.


 * [[Image:Spell Nature ChainLightning.png|32px]] Chain Lightning - Deals 5550 to 6450 nature damage on heroic or 4163 to 4837 nature damage on normal. Can chain onto an additional target within 10 yards up to five targets. Spread out to avoid chaining this ability. Can be interrupted and is affected by effects which increase casting time.
 * [[Image:Spell Nature WispSplode.png|32px]] Overload - Similar to Loken or Murmur this 6 second channeled spell deals 25,000 nature damage on heroic or 20,000 nature damage on normal to all targets within 20 yards of Brundir. Brundir generates the emote "Stormcaller Brundir begins to Overload!" while casting. While casting gains the Stormshield effect which deals 250 nature damage and grants immunity to stun effects.
 * [[Image:Spell Nature WispHeal.png|32px]] Lightning Whirl (1 dead) - Deals 5655 to 6345 nature damage on heroic or 3770 to 4230 nature damage on normal per bolt. Fires multiple bolts per second and needs to be interrupted as quickly as possible.
 * [[Image:Spell Nature LightningOverload.png|32px]] Lightning Tendrils (2 dead) - Brundir lifts off into the air and gains an aoe ability that deals 5000 nature damage per second on heroic or 3000 nature damage per second to all targets in close range. Will randomly switch targets and needs to be kited away from the raid to minimize damage. Raid members should spend this portion of the fight keeping as far away from Brundir as possible. Resets aggro when he lands.
 * [[Image:Spell Nature LightningShield.png‎|32px]] Stormshield (2 dead) Brundir also becomes immune to stun effects once Steelbreaker and Runemaster Molgeim are dead, as he is not previously. Stun effects against him before this are affected by diminishing returns however.

Phase 1: All three alive
Players can choose to kill the trio in any order they wish, though the popular and easiest route is Steelbreaker, then Molgeim, then Brundir. Be warned that when you kill a boss, the remaining bosses will return to full health. This prevents the raid from being able to take down multiple bosses at the same time.

Just like Maulgar, Illidari Council, Karathress, etc. all of these bosses have to be pulled and tanked away from each other in precise positions. Molgeim and Steelbreaker can be tanked in the two front corners of the room, but Brundir must be tanked towards the back for his Overload (30 yards) which will deal a lot of damage to anyone that is not a tank (often times killing them). Note that Brundir's tank can simply eat the Overloads, since the tank should have a dedicated healer, otherwise only doing raid healing. If it is an issue, the tank should move away as well, then move right back to Brundir when the channeled cast is over. Any casters and the tank on Stormcaller Brundir that can interrupt should be interrupting Chain Lightnings whenever possible. The healer assigned to Brundir's tank should be close to Steelbreaker's back when the fight begins, 35+ yards away.

Molgeim will often put a Rune of Power underneath either Steelbreaker or Brundir so they must be pulled out of the rune far enough to where they're no longer benefiting from the buff and melee or ranged players can bunch up in this rune and output higher damage upon the primary target.

Steelbreaker on occasion will deal a Fusion Punch which the tank must call out for focused healing and a magic dispel of the nature debuff that is inflicted from the punch. Use either a Paladin's Cleanse, a Priest's Dispel Magic, or a Warlock can use their Fel Hunter pet and use Devour Magic on the tank. If you are killing Steelbreaker first, melee must bunch up to benefit from Circle of Healing, Chain Heal and Wild Growth used to counter the nature aura damage.

Phase 2: One Boss Dead
When one of the Iron Council dies, the other two will gain additional abilities. For the most part, they will be tanked in the same general areas but these new abilities will compensate for the dead boss.

Steelbreaker will gain Static Disruption which will cause a random raid member not in melee to take 75% more nature damage for 20 seconds. The whole raid will need to be spread out as this is an aoe and will be extremely irritating to heal through if it hits more than one player.

Molgeim now has a Rune of Death, which will be cast on a random raid member. It is a big, green rune that is impossible to visually miss. Melee and ranged must bunch up and be ready to move in the same general path to avoid confusion, splitting up, and getting out of range of heals.

Brundir will gain Lightning Whirl, which animates like whirlwind and will shoot random lightning bolts at raid members which will deal a large amount of nature damage to random raid members. It can, and should, be interrupted.

Phase 3: Two bosses dead
When two of the three bosses are dead, the last one will separate into a unique phase different from their usual abilities in the previous phases. Players must be alert during this phase because elements are introduced that will almost instantly wipe the group if they don't coordinate around them.

Steelbreaker
Blow Bloodlust/Heroism and hit Steelbreaker with an almost impossible amount of DPS to kill him before you run out of tanks due to Meltdown. The DPS and healing requirements of this achievement are extremely high so it is not recommended for most groups.

Runemaster Molgeim
Molgeim will open up a Rune of Summoning (purple void zone spawn akin to the voidwalkers in TBC) which will spawn lightning elemental adds which will explode for a high amount of damage to anyone within 30 yards when they reach their aggro target. They spawn one at a time, but up to 8 or 9 adds total will be spawned rapidly. They are tauntable and will race after the random players, but they can be taunted by tanks for an emergency target switch. Improved Blizzard and Earthbind Totem DO work on the lightning elementals. All players should move as far from the zone as possible, dropping AoEs in prep for the add arrivals. All AoE helps, however every effort should be made to avoid meeting the adds in melee. If an add bolts free of the AoE, targeted members should run while ranged helps dps down the loose add. Good communication and proper reaction to the add spawns is essential. Also to note, while not necessarily safe, melee dps can help kill the adds as long as one is not chasing them, although it is preferred to let ranged dps take down the spawns.

Stormcaller Brundir
Brundir will lift up into the air and gain Lightning Tendrils. Anybody within a 10 yd range of Brundir will get hit by these tendrils for high nature damage; standing near him for more than a couple of seconds will prove fatal if you are not a tank. He is tauntable, but will clear aggro every time he lifts up into the air, and taunting during Lightning Tendrils will not change his target or course. Occasionally he will fall to the ground and melee can move in to attack, but he will lift again without warning and hit them with his tendrils.

Steelbreaker

 * Aggro
 * yell


 * Special
 * yell


 * Killing a player
 * yell
 * yell


 * Berserk
 * yell


 * Death
 * yell
 * yell

Runemaster Molgeim

 * Aggro
 * yell


 * Rune of Death
 * yell


 * Summon adds
 * yell


 * Killing a player
 * yell
 * yell


 * Berserk
 * yell


 * Death
 * yell
 * yell

Stormcaller Brundir

 * Aggro
 * yell


 * Special
 * yell


 * Taking flight
 * yell


 * Killing a player
 * yell
 * yell


 * Berserk
 * yell


 * Death
 * yell
 * yell

Sound Files
See Sound Files of Ulduar: Assembly of Iron

Drops
The Archivum Data Disc / Archivum Data Disc (Heroic) also drops if runemaster Molgeim is killed last.

Related achievements


The following achievements are for the encounter's hard mode.

10-man encounter
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25-man encounter
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25-man Hard mode encounter
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