World of Warcraft: Assembly of Iron 10/25 Ulduar Raid Guide

The Assembly of Iron, often colloquially called the Iron Council, is the 5^th boss in Ulduar.

The Assembly of Iron consists of 3 unique bosses. Unlike other multi-enemy raid bosses, they do not share HP and surviving bosses heal to full when others die.

This means that players need to work together and focus on one at a time. They also gain more damage and abilities.

Coordination between players is vital to take them down. This guide will give you an overview of the general strategy for the fight in its Normal and Hard variants.

Assembly of Iron 10/25 Ulduar Raid Guide for World of Warcraft

As mentioned at the start of the article, the Assembly of Iron consists of 3 bosses. The iron giant Steelbreaker, the iron vrykul Runemaster Molgeim, and the iron dwarf Stormcaller Brundir.

When one of them goes down, the other 2 will heal fully and gain a Supercharge buff. This gives them a 25% damage increase and gives them new mechanics and abilities.

The fight’s difficulty depends on which order players take them down.

The fight’s Normal variant is done when killing Steelbreaker first, then Molgeim second, and Brundir last.

Conversely, the Hard variant has players killing bosses in the reverse order. This means Brundir should be killed first, Molgeim second, and Steelbreaker last.

You generally want 2-3 tanks, 4-5 healers, and as many DPS as possible. The strategies in this guide should work for both 10 and 25-man raids.

Now, let’s go over both versions of the fight.

Normal Fight

For the start of the fight, players should first decide their tanking strategy.

A more traditional approach has one tank on Steelbreaker and another tank dragging Molgeim and Brundir away from the raid to avoid Overload.

Another popular strategy, however, is to have all tanks stacked. This allows the raid to better control where Molgeim will use Rune of Power and also allows them to deal more damage.

However, everyone will have to make sure to avoid Overload every 30 to 60 seconds.

Also, take note that most damage in this raid comes from lightning abilities. Aspect of the Wild and Nature Resistance Totems are essential here.

With either tanking strategy in mind, players focus on Steelbreaker. His attacks can’t really be avoided and have to be tanked.

Fighting Molgeim

Once Steelbreaker is down, Brundir and Molgeim both gain full health and one stack of Supercharge. At this point, a tank should draw Molgeim away from Brundir.

Meanwhile, the others should focus on killing Brundir.

Molgeim spawns a Rune of Power at the feet of one of his allies every 30 to 60 seconds. This appears as a blue rune on the ground and increases damage from all units by 50%.

Tanks should draw the bosses away from the rune without going too far from it. Players should take advantage of the rune’s buff by standing inside it.

At times, Molgeim will cast Shield of Runes to protect himself. This shield absorbs 50k damage and also buffs him when broken.

Mages can ideally steal it with Spellsteal but it can also be Purged before it’s broken. Avoid breaking it.

Due to Supercharge, Molgeim can now also spawn a Rune of Death every 30 seconds. This does 3500 shadow damage every 0.5 seconds to any player inside it.

If the raid is inside the Rune of Power, the Rune of Death will make it unusable. Players should coordinate to get out of the Rune of Power before Molgeim casts the Rune of Death.

Healers should be spread out for safety but also to try to bait the Rune of Death away from the raid.

Dealing with Supercharged Brundir

With Molgeim finally down, Brundir gains a second stack of Supercharge. This gives him a total 50% damage buff and 3 new abilities.

Brundir casts Chain Lightning frequently, which bounces between up to 5 raid members dealing around 6000 nature damage. Interrupts and stuns can stop it, but it’s not a high-priority threat.

The real annoyance from Brundir is his Overload ability. Brundir channels the ability for 6 seconds and then explodes.

This deals 20k nature damage to every player in a 20 yards radius and also stuns them. This damage is without accounting for his Supercharge buff! Avoid the explosion at all costs.

One of Brundir’s additional abilities from Supercharge is the Lightning Whirl. Brundir will spin and damage a dozen random players for about 4.5 seconds.

This is a high-priority threat and it’s important to focus on interrupting its channeling ASAP.

He also gains Stormshield from the second stack of Supercharge. This is a permanent buff which makes him immune to stun. It also makes him reflect some damage to melees with every hit, as 250 nature damage.

Finally, his last new ability is Lightning Tendrils. He uses it a minute after gaining the second Supercharge stack.

Brundir takes to the air with lightning coming off of his body. He will focus on chasing a random player while doing this. He deals 7.5k nature damage every second to anyone within 18 yards.

The player he chases should kite him and survive for 25 seconds. Melees should back off until he stops his rampage.

At this point all that’s left is to keep damaging him and surviving until he goes down, ending the raid.

Hard Mode Fight

The Hard variant of the fight is pretty similar at first.

Players should focus on Brundir first, at which point he only has Chain Lightning and Overload, making him much easier than on the Normal fight.

After Brundir goes down, Molgeim is up next. The fight is pretty much the exact same as the Normal fight.

The real challenge comes in when Molgeim is taken down and you’re left with a fully Supercharged Steelbreaker!

Fully Supercharged Steelbreaker

Steelbreaker’s damage is already scary from the get-go, so the 50% damage buff from Supercharge makes him a force to be reckoned with. Not to mention his ridiculous new abilities.

The first stack of Supercharge unlocks Static Disruption. Steelbreaker will shoot lightning at the furthest target every 10 seconds.

This deals 7k nature damage to the player and anyone close to them. It also applies a debuff that increases nature damage taken for 20 seconds by 75%.

The easiest way to deal with Static Disruption is to spread out healers far away so that it targets them. He won’t shoot Static Disruption at the same target twice in a row so it will cycle through available targets.

When Steelbreaker is alone and has two Supercharge stacks, he unlocks his last 2 abilities.

From now on, he will heal back 4 million HP anytime a raid member goes down. This can be cut down to 20% with Mortal Strike, Aimed Shot, or Wound Shot. Even scarier, he gains a stack of Electrical Charge too.

This is a 25% damage buff which stacks with the 50% buff he already has from Supercharge.

Additionally, he will buff tanks with Overwhelming Power. This gives the tank a 200% damage buff. After 25 seconds, the buffed tank will suffer from Meltdown. This instantly kills the tank and deals 30k damage in a 15 yards radius.

Tanks that were targeted by Overwhelming Power should swap with other tanks and separate from the raid to avoid damaging them with the explosion. Soulstone tanks so they can be revived.

DPS Race Against Steelbreaker

As you may realize at this point, Steelbreaker will kill a tank every 30 seconds. There is no way to avoid this, making the fighting a pure DPS race as players try to burn through his huge HP pool quickly.

Steelbreaker’s Electrical Charge buff doesn’t wear out. After he has killed 2 or 3 tanks, his damage output will simply become impossible to survive.

A trick to reach the insane DPS required is to leave Molgeim alive with a meager amount of HP until he casts Rune of Power. Quickly finish him off when he casts it and then use the rune to go all out against the Steelbreaker.

Now that you know every dirty trick these bosses have up their sleeves and how to avoid them, you should be ready to take them down.

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