This encounter involves defeating the three members of the Iron Council; Steelbreaker, Runemaster Molgeim and Stormcaller Brundir. Obviously the hardest part of this encounter is surviving against all three of them, as the combined damage they deal is extremely heavy. From a soloing perspective, when one of the three dies, the rest of the fight becomes a lot easier, however back then it wasn't so much the case, as the remaining members each gain a new ability each time one dies. The actual ability itself is determined by which one remains alive.
With that said, it has been determined that killing Steelbreaker first, Molgeim second, and Brundir last is the easiest way to go, and this was deemed as the "normal mode" way to do the encounter. Killing the bosses in any other order would thus be considered "hard mode", with killing Steelbreaker last being the "hardest mode"...apparently. Since this is my first time soloing this encounter, as well as the fact that I ain't a DK or a hunter, I decided to just stick to the easy mode way.
The fight starts off with very heavy melee damage from Molgeim and Steelbreaker, combined with some mild damage from Brundir. Thus Brundir can be pretty much ignored at this point. The main things to watch out for are:
1. Steelbreaker's Fusion Punch. This deals an initial damage of 15k, with an additional DoT that ticks for 15k every second for 5 seconds. The DoT must either be dispelled immediately or Dispersed through.
2. Molgeim's Rune of Power. Molgeim created a blue rune of power underneath one of his allies. The rune increases the damage dealt by anyone standing on it by 50%. If the rune is summoned underneath Brundir, there is nothing much that can be done. But if it was summoned underneath Steelbreaker, he (as well as Molgeim himself) must be kited out of it ASAP. Note that I tried to stand (on the edge) within the rune myself, so that only I get the buff whereas Steelbreaker/Molgeim doesn't, but this strategy failed as Steelbreaker's hitbox size was so large that it always seemed to overlap mine, hence we both get the buff.
Aside from those 2 things, Runemaster Molgeim also casts a shield on himself that absorbs around 20k damage on 10man. If the shield is completely used up, Molgeim will gain a 50% damage buff for 15 seconds. This however, does not have any effect on the fight as the primary target at this point is Steelbreaker so there shouldn't be any damage done on Molgeim. However I am only mentioning this because there might be some people who use the Cunning of the Cruel trinket, that can deal incidental damage to Molgeim. It is also important to keep DoTs up on Steelbreaker. But don't do so until you have enough health to take the next few blows without heals. Be patient, the enrage timer is quite generous.
Once Steelbreaker falls, the fight becomes significantly easier. Both Molgeim and Brundir will each gain a new ability, but that is nothing compared to the fact that there is now 1 less boss to deal with. Brundir gains a lightning whirl ability, which is like Mind Flay, except it's Lightning, and that can be totally ignored. Molgeim will now cast a Death Rune on the ground which is similar to Death and Decay, and this can be dealt with by simply running out of it. At this point, start focusing on Molgeim. Keep DoTs on him but watch out for his shield. Dispel it immediately after he casts it. However since it only absorbs around 20k, it probably won't last long enough for you to react, especially if all 3 DoTs are ticking. So keep your health above 50% at all times. If mana is low, you may want to deliberately dps through the shield since his buffed damage can trigger Masochism.
After Molgeim is down, victory is pretty much guaranteed. Brundir is the easiest out of all three despite gaining his 2nd new ability, Lightning Tendrils. He floats up in the air, and sends tendrils of lightning bolts down from above. Although it looks devastating, a simple PW:S can pretty much absorb the entire thing zzz. Anyway just finish the boss and collect the loot.