This is part of a series of posts about the role of rogues in Ulduar. The focus is on 10-man raids, but on occasion mention will be made about 25-man strategies as well. This is not meant to be a general strategy guide. It is completely targeted at rogues, their abilities, and their strengths in specific combats. Much of what is written could apply to other melee dps as well.
The Assembly of Iron (or Iron Council, as it is often called) is a group of three bosses. It has a very unique mechanic in that the order that you kill them determines the difficulty of the encounter.
The largest of the three is Steelbreaker. The medium-sized one is Runemaster Molgeim, and the small one is Stormcaller Brundir. The neat part about this fight is the way it gets progressively harder. When the first of the three is killed, the remaining two get stronger and gain new abilities. Then when the second one is killed, the last one gets even more new abilities. Thus, the order in which they are killed completely determines the strategy. This guide is for “normal” mode, which is to kill Steelbreaker, then Molgeim, then Brundir (that’s from largest to smallest).
All three need to be tanked. In 10-man, Steelbreaker and Molgeim can both be tanked together by one well-geared tank, and Brundir gets his own tank and healer far away from the rest of the raid. Or if you have an extra tank Molgeim can be off-tanked on his own. Brundir does a lot of AoE and ranged damage, so one tank and one healer will take him all the way to the back out of range of the rest of the raid. Brundir is stunnable and interruptable, so a warrior tank does well with that.
The first to die is Steelbreaker (the big one). He is mostly tank-and-spank. Periodically he will cast Fusion Punch which is a buff on himself, and he can wreck the tank with that. It must be dispelled, but its not interruptable so there’s nothing that rogues can do here. We just stay on the boss and dps hard and hope that the dispellers are doing their thing. There is an aura from Steelbreaker doing nature damage, and you can reduce the damage with Feint to help the healers if they are having trouble, but it shouldn’t be necessary on 10-man because the damage is not severe.
Throughout this first part of the fight, Molgeim is casting Runes of Power on the ground. The runes will give a big damage buff to whoever stands in them. He will sometimes cast it underneath Steelbreaker, and the tank will drag the boss out of the rune. But the rune stays on the ground. The ranged dps will all cluster in the rune and get buffed. Can rogues stand in the rune? Yes, but only if the tank is careful how far he moves the boss. So you might discuss this with the tank in advance. See if he can move Steelbreaker only as far as it takes so he loses the buff.
If he moves the boss too far, then the ranged dps gets to stand in the rune and we don’t. In that case, don’t expect to top the meters on this fight. Ah well. Can’t win em all.
So after a few minutes, Steelbreaker will die. Next up is Runemaster Molgeim. He still drops his Runes of Power and he also has a Shield of Runes. That absorbs damage, and if it absorbs its maximum damage (20k) then the boss gets a damage buff. Hopefully someone in your raid will dispel that or spellsteal it. Again, there is nothing that rogues can do about it. Just stay targeted on the boss.
When Steelbreaker died, Molgeim gained a new ability called Rune of Death. This is a HUGE green rune that he places on the ground that ticks for very heavy damage (about 7k per second). When you see the green rune appear on the ground you have to get out of it ASAP. If your reactions are slow, use Sprint, or Cloak, or Feint to reduce the damage. Then run around it and get back on the boss. Maintain time on target as much as possible.
When Molgeim dies, everyone turns to Brundir. He has an assortment of electricity-based abilities. However, he is interruptable so be ready with your Kick. Also, it may be worth your time to quickly switch to Mind-Numbing Poison for this fight to slow his casts. Brundir was stunnable earlier in the fight, but once the other two bosses are dead he gains Stormshield which makes him immune to stuns, but not interrupts.
Brundir frequently casts Chain Lightning. Try to interrupt that to minimize raid damage. His big damage ability is Overload, which is much like the corresponding AoE explosion from Loken or Emalon. It has a long cast, and when it goes off it does 20k to anyone near him. He can’t be interrupted while casting this, so you’ll want to run out. If your reactions are slow you can Cloak to avoid the damage.
Since his two friends died, he has gained new abilities. He does a powerful Lightning Whirl that will fire out bolts of electricity at a high frequency. Kick that to stop it. Make this a priority to interrupt.
His final ability that he gained from his partners dying is Lightning Tendrils. You can’t miss it. He floats up in the air and gets all these spidery electricity legs arcing down to the ground. Its very cool looking. He targets someone and follows them. Its easy to avoid. Just run away. Bandage while you are far from him.
When Brundir is the last one up, you just Kick him whenever he casts, run out of the Overloads, and run away if he floats up in the air. Its actually the easiest part of the fight, in my opinion.
The fight has a fifteen minute hard enrage timer. It is a fairly long fight, but very interesting. Once you have done it with the order listed above, you can try it with other sequences. Hard mode is to leave Steelbreaker for last, in which case he gets to auto-kill of the tank once every 60 seconds. Of note for rogues – if you ever fight Brundir when he is not the last one up, then he is stunnable. In those fights, you will want to get him locked down with all of the stuns in your arsenal.
A note: if you can pull off Hard Mode on either 10-man or 25-man you’ll have a shot at a couple of the best daggers in the game. 10-man Hard Mode offers the Perilous Bite, and 25-man Hard Mode has the Fang of Oblivion (best in slot MH dagger).