Here we are, once again, on the final leg of our journey. Dark brothers and sisters, at least we reach the final (non-heroic) challenge of raiding content; Cho'gall! Alas, he isn't all that he is cracked up to be. If you have managed to clear the rest of the Bastion of Twilight -- which you rather have to in order to get this far -- then you shouldn't have many issues with this encounter.
As with everything in raiding, certain battles are more difficult in one raid size than they are in others. For Cho'gall, going along with 24 other makes the encounter far easier than doing it with only 9 other people. It's just another one of those things that you have to take it for what it is. I wish you luck in this encounter. Oloth plynn dos!
The first thing of note about fighting Cho'gall is the Corrupted Blood mechanic. Much as with Atramedes, players are given a new bar at the start of the encounter; this time, it measures your level of corruption by the Old Gods. Getting hit by virtually any ability during the encounter adds to your corruption meter; nearly all of it is avoidable during phase 1. There is no way in which to reset your level of corruption, so you must do your best to avoid being hit by anything nasty as best you can.
The bar itself has four large bubbles in it; these mark each degree of corruption that a player has. Every time a bubble is filled, that player reaches a new level of corruption and is hit with a new affliction.
- 25% You gain Corruption: Accelerated, which needs to be removed immediately.
- 50% You gain Corruption: Sickness, dealing damage to anyone 5 yards in front of you. Turn so that you are not facing other players.
- 75% You gain Corruption: Malformation, causing a tentacle to sprout from your back that attacks random players with Shadow Bolts. Cannot be killed, must be healed through.
- 100% You gain Corruption: Absolute, reducing incoming healing by 100% but also increasing damage by 100% and making all spells instant.
It is entirely possible to get through all of phase 1 without reaching even 25% corruption. This should be your goal for the encounter. If you are reaching phase 2 and are already at 50% corruption, then you have done something seriously wrong and you will more than likely reach 100% and die soon after.
This phase encompasses the bulk of the encounter, lasting from 100% until 25% of Cho'gall's health; however, it is actually the easiest of the two phases. During this phase, there's a wide array of abilities that will be thrown at the group.
- Flame's Orders One of two "stances" that Cho'gall can be in. Each attack deals additional fire damage to the tank. Pools of fire, which must be avoided, also spawn on the ground.
- Shadow's Orders The other "stance" that Cho'gall can take. Three pulses of shadow damage that deal damage to the raid will be emitted during each Shadow's Orders.
- Conversion Mind-controls several raid members and causes them to channel Worship; broken when the player is interrupted by any means -- CC, stun, interrupt, anything.
- Fury of Cho'gall Increases the physical/shadow damage taken by the tank; requires a tank swap to deal with.
- Summon Corrupting Adherent Does exactly as the name implies: summons a Corrupting Adherent add, which must be tanked and killed.
- Corrupting Crash Used by the Adherents, this shoots out a shadow bolt bomb that needs to be avoided.
- Depravity Used by the adherents, this deals AoE damage to the raid; needs to be interrupted.
- Festering Blood Summons Congealed Blood of the Old Gods from either dead or living Corrupting Adherents.
The flames that spawn during Flame's Orders are rather insignificant; they spawn in random locations, not actually on players, so more often then not you won't even have to move to deal with them. If they do happen to spawn near the raid, you absolutely must avoid them at all costs. The timing of Fury of Cho'gall is such that it should always occur just before an add is spawned, so you should never have to worry about needing to tank swap while an adherent is up.
Conversion will be the most annoying mechanic of this phase, causing a varying number of players to start channeling Worship, which buffs Cho'gall. This is one of the mechanics that makes 25-man that much easier than 10s. Just about any CC or interrupt ability will stop Worship -- which would be Fear, Spell Lock, or Shadowfury for you -- and needs to be used immediately. The blood elf or tauren racial also works wonders for this; not that there are cow warlocks, but there should be!
Congealed Blood This is the "soft enrage" of the phase. For every adherent that is spawned, four Congealed Bloods will be created from its corpse or living body every time Festering Blood is cast. For this reason, you really want to have all of the adherents die in relatively the same location. The back of the room where you enter is the best spot for this. Have your tank drag the add up the stairs and kill it there. Once dead, the adherents leave a pool of blood that will hurt like a monkey if you stand in it.
The first add spawn isn't too difficult; there only being four Bloods at this point. You should only need one to two DPS in 10s or two to three in 25s in order to take them out. After that, it can start to get tricky, and you'll want to have all of your ranged attacking the Bloods after the first spawn. Melee should avoid them if at all possible, because a single hit from a Blood is worth a ridiculous amount of Corruption.
This is yet another reason why 10-man is much harder than 25-man. You need to slow/push back the adds as much as possible to buy the time you'll need to burn them down; you'll have many more options for this in 25s than in 10s. You are also going to have access to more ranged DPS in 25, which makes adds that much easier.
A raid generally won't be able to handle more than four casts of Festering Blood -- which would spawn 16 adds by that point -- so you want to avoid getting any more adherents than that. Any active adherents will despawn once Cho'gall enters phase 2, so ignore the fifth add and push Cho'gall if you have to.
Destruction tips Unfortunately, I have to say that if you aren't destruction for this encounter, then you are seriously hurting the raid. Shadowfury is simply that amazing. I know, I know, there are so many ways that interrupt Worshiping that it shouldn't really matter, but it does. Shadowfury will be available for every single Conversion cast, and it will instantly stop every single person hit by it.
Even though there are other abilities similar in power to Shadowfury for this effect, a raid really needs to have as many of them as possible. 25-man has five people hit with Conversion every time, so if you only have four AoE interrupts, then all four of those players could be the ones picked. It'd be horrid luck, sure, but you really just don't want it happening -- and it's more of a risk in 10s.
Aside from that, you'll want to put up Bane of Havoc on Cho'gall once the adherent spawns and keep it active until after you've killed the Congealed Bloods. There should be enough time between the Bloods dying and the next adherent spawning that you can get a full Bane of Agony off on Cho'gall during the in-between time. When it comes to AoE, you'll just want to tab+Immolate spam and use Conflag on cooldown; if you are on the first two packs, you can stop and hard cast a few Incinerates or a Chaos Bolt once you have Immolate rolling on every target.
When switching to the add, Immolate it, and then re-target back on Cho'gall as the add is positioned. Start moving to DPS the add once it gets around three-fourths of the way to where it will be tanked, and spam Fel Flame on Cho'gall while you move, then switch to the add either once Cho'gall is out of range or you get close to the adherent. Continue to spam Fel Flame until you are in a good spot to stop and resume a standard rotation. (Conflag on cooldown, of course.)
Affliction tips Soulburn: Seed of Corruption is useful once you get to the third and fourth Blood spawn -- you can use it on the second spawn too, but be careful to target one of the back adds so ensure the detonation goes off. You probably shouldn't be assigned to handle the first Blood group, but if you are, just tab-DoT the adds as you can.
Use Glyphed Soul Swap to get your DoTs rolling on the adherent as it spawns, and from there, just follow your basic, standard rotation to kill it. Don't forget to Soul Swap the add once it gets low on health so that you can get everything rolling back on Cho'gall, too. Ideally, you never want to let your DoTs fall off Cho'gall, but the first two adds should have you out of range of him while you are killing them, so you may not have a choice.
Follow the same movement strategy as destruction above while moving to and from the add; you should, however, be teleporting back to Cho'gall and be able to instantly resume normal DPS procedure after the adherent is dead -- or start nuking Bloods.
Demonology tips Sadly, this is one encounter in which I would strongly advise against using demonology. Although the spec has very potent AoE (especially compared to the other two), it puts you far too close to the adds to use safely for my comfort. It can be done, but I would put it in my "risky" column, and I'm simply not a risk-taking player in these situations.
One benefit that you do have is that you can summon a Hand of Gul'dan on top of the group of adds and then send your Felguard in to do a rather strong Felstorm for rather decent AoE damage. Aside from that, you will mostly want to leave your pet attacking Cho'gall, making sure to drop a HoG just before running off to kill the adherent. If your adherent DPS is too low -- which can happen in 10s -- then you will need to switch your pet as well.
Good news is that you should use the adherent and any low-health Bloods to proc Decimation, to allow you to rip some fast-paced Soul Fires into Cho'gall after it's all said and done.
Once pushed, Cho'gall will cast Corruption of the Old God, causing constant AoE damage to the raid. All of his phase 1 abilities except Fury of Cho'gall are gone during this phase; however, he will now cast Darkened Creations. At this point, you will want to pull Cho'gall toward any wall in the room. Previously, pulling him to his throne was the best option, but the recent patch changed this. Taking him to a wall. however, still makes the spawn location of the Creations far more centralized than leaving Cho'gall out in the middle of the room, so it is worth moving him.
The Creations need to be killed as soon as they spawn, and quickly. They deal ridiculous amounts of damage while alive, and they will make healing excessively difficult if allowed to free cast on players. Most of them will be too far spread out for any traditional AoE spells; however, you should still be able to get a good number of them within a HoG ring and should switch your pet to assist in bringing them down.
If you usually rely on tabbing to switch between multiple targets, then I would advise against it here and suggest that you use enemy health panes instead. Using tab tends to default to Cho'gall rather often, when you really want to be targeting one of the adds that are up.
This phase is really about pushing DPS and managing to survive. People will start hitting 50% corruption at some point during this phase, so you really need to make sure that your raid loosely spreads out to avoid puking on each other. Healthstones are also extremely useful during this phase -- and if you feel really nice to your healers, you can Soulburn one for some extra life for a while, but it isn't needed.
My last bit of advice for this phase is to not grow overconfident! Even if you have Cho'gall at 5%, don't think that you can just ignore the adds. They will rip through a raid in a matter of seconds if left alive, and Cho'gall has quite a large amount of health to eat through. Don't ignore the Creations until you are at least at 2% -- and even then, you may want to have your rogues, shaman, and death knights peel off to interrupt.
Best of luck to you!
Blood Pact is a weekly column detailing DoTs, demons and all the dastardly deeds done by warlocks. We'll steer you toward tip-top trinkets and Soulburning your way through Cataclysm.