Heroic: Four Kings

Tactics (10m, most will apply to 25m as well):

I assume that you're familiar with the normal mode, so let's start with the differences:

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• Everything hits harder and every mob has more HP, as usual
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• When one of the (first three) Spirit kings reaches 30% HP, the next one will spawn
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• Every Spirit king has a dispellable, very dangerous self-buff
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• Flanking orders will start two groups of soldiers instead of one
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What do these changes mean for the raid?

First of all, with today's gear the boss is easily managable with 1T 2H in 10m. Therefore, you probably won't have any real problems with the enrage timer. Unfortunately the reason for being 2-healable is not that there is not much damage, but that most of the problematic damage (like being hit by Flanking Orders or Annihilate) is simply deadly. This is a dancing boss, either you don't get hit by stuff or you die.

Phase by phase:

Qiang the Merciless:

The combination of double Flanking Orders and Massive Attacks will force you to very coordinated movement. We had our tank call out a direction and stick to it. Furthermore, when the boss reaches 30%, at least three of your ranged/healers have to spread out due to Rain of Arrows, making stuff even more dangerous. Therefore it is recommended to dispell the second Impervious Shield right before the boss hits 30% to burn him down before the third one. In general, the intermediate phases with two bosses alive are by far more dangerous than the single bosses (this is somewhat obvious, but still worth mentioning that using heal and personal cds, heroism and pots all should happen in these phases).

Subetai the Swift:

We had the luxury to have enough people able to free themselves from Rain of Arrows (Humans, Paladins, human Paladins and a Mage!). If you don't get hit by Volley more then once, you're fine until the next boss starts. Pillage is extremely easy to run out off. Sleight of hand is easily dealt with if you have two stunners who will cover most of the time the buff is up. I personally had the feeling that applying dots and keeping up channeling spells didn't even trigger it.

Zian of the Endless Shadow:

His Shield of Darkness allows no fails at all and has five charges, dispell it asap. This is especially evil while you're burning down Subetai. We used heroism for the final 30% right after a Shield. Also, we stopped damage on the adds as well when a shield was up - better safe than sorry.

Meng the Demented:

His enrage effect (Delirious) must be dispelled fast, and everybody has to watch out to not kill him/herself to the reflection effect of Cowardice at high energy levels. Something that wiped us twice on seemingly safe kills was Maddening Shout in combination with a respawning add from Zian. While in theory you could easily spot them early enough there is so much flying around in the final phase that it's easy to just follow your tank's "group up!" command and die horribly. Just stay cool and reap your rewards.

Have fun!