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 , , and . 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 . Strategy . 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 . With good timing a melee dps could taunt from across the room right before the 2nd boss dies to pick up the damage buff and sacrifice himself . Of course should the tank taunt back immediatly after the buff is taken . this can be repeated , right before the debuff time runs out to ' sacrifice ' the next dps . . this increases the time the raid have for the last boss and puts damage buffs on one dps . 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 . Quotes . Sound Files . See " Sound Files of Ulduar : Assembly of Iron " Drops . The / also drops if runemaster Molgeim is killed last . Related achievements . The following achievements are for the encounter ' s hard mode .