A decent guide, I have one criticism.

You take the time to note that Mage-Lord Ulom can be zerged down by a sufficiently geared group, but make no such mention for the first two bosses. In fact, Ulom is the most dangerous of the three thanks to the perfect storm generated by his abilities.

The damage done by Drakos the interrogator is so low that I almost always cast Earth Shield and DPS without casting another heal. Even in undergeared/skilled groups, people rarely go below 80% of their health. There's similarly no reason to run away from him following a magic pull, as he'll simply pull you right back in. Just zerg him down.

Varos Cloudstrider is more dangerous thanks to Amplify Magic, but ultimately he too can be zerged down without much issue. It's good practice to avoid the cone of damage and the lazers, but rarely necessary. The biggest risk here was accidentally aggroing Drakes, which was made nearly impossible by Blizzard.

Ulom, however, will kill even good groups if they get sloppy. Most groups that try and Zerg him down do not have the sense to move him behind a pillar as a precaution, and as such when he teleports the tank and all the melee find themselves as far from a pillar as possible in the middle of a frost patch. This is often lethal.

Even if it isn't, by this point all the melee will have stacked the Frost Bomb debuff to a dangerous level. This places a huge strain (relative to heroics) on the healer. If they are not prepared or geared, you can easily lose members who survived the Arcane Explosion.

Finally, even if the healer manages to barely keep the group alive through that, a single well placed Time Bomb can spell disaster. The damage done is equivalent to the difference between the debuffed player's current and maximum health. A 50k health tank with 10k health will instantly kill everyone nearby when it goes off.

If you're remotely concerned about zerging the first two bosses, you shouldn't consider zerging Mage-Lord Ulom.

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