As for what abilities you need to be aware of (beyond knowing everything about everything) it comes down to spores once again. Like Loatheb, you want to have a spore burst itself over you, except this time the penalty for failure isn't less damage and threat problems but choking to death on the putrid effusions vented from an undisclosed orifice of this abomination. Lets run through the fight:
Your tank runs in waving their weapon wildly and shouting incomprehensibly, you step more calmly into a position and start destroying the beast. You want to make sure you are spread out somewhat (at least 8 yards) from the other ranged bods -- though not too much as you'll see. The separation is to avoid overlap on the Vile Gas ability. This is similar to the conflag ability used by Grand Astromancer Capernian in that it disorients the target and isn't good to be near.
So, that's your 'spread-out' mechanic and where there's one of those there is usually a 'gather together' mechanic too. In this case it's those spores. Spores will spawn over the heads of two (10 man) or three (25 man) raiders, twelve seconds later they explode covering you in... well, lets not think about that, whatever it is it gives you 25% resistance to shadow damage. This buff stacks up to three times and you're going to want all three.
The gas all through the room does shadow damage which DoTs away at you for various amounts depending on the amount of gas in the room. This is all fine and frankly it's the healers problem, not yours. The gas gets inhaled by the boss every thirty seconds or so and then every two minutes he lets rip and fills the room again. This seems to take your senses somewhat by surprise and just like in the proverbial elevator, there is no escape. This Pungent Blight deals between ~44k and ~ 75k damage (10 man normal and 25 man heroic, respectively), so if you don't have some serious resistances or immunity you are going to be reduced to a stinky mass on the floor.
For 10 man this is done by having one of the spore carrying people on the melee/tank group and the other at range, with everyone stood on top of them. For 25 man it's the same but with two ranged groups. You need to get together quickly and gain the Inoculated buff, then spread back out to your positions. Circle is a good means of getting back to station but as you don't know where the spore will be you can't use it to get there. In normal modes it is possible to survive only having two stacks of Inoculated, but only just. Soul Link makes it easier for demo locks but we don't have any immunities like those sneaky mages or priests so we really need to just get it right.
If you can stay alive, do the dance and deal the damage then this fight is in the bag.
This is now my favorite fight in ICC, there's so much going on and the boss emotes just never get old. Once again, we see the formula of two opposing boss mechanics -- A load of sh... stuff on the floor that you don't want to move into and a couple of things that make you want to move about.
First off, and most obvious, are the big vats of green slime around the room. These will cover a little under a quarter of the room at a time in... again, best not to think about exactly what it is but it's green and on the floor so you don't want to stand in it. We found the easiest way to station your ranged players was in a circle around the boss (who's in the center of the room) as far as possible away from him without ever being in the goo. This meant that when he did his delightful Slime Spray ability fewer people got hit by it but the ranged don't have to move all the time and can keep the DPS high (suck it up, healers).
So, that's the Ooze Flood and Slime Spray covered, that only leaves Mutated Infection. This is where it gets interesting. So, you get infected (you really don't have to worry about anyone else being infected), this will do damage over time and reduce the healing you take by 50%. After 12 seconds (or when cleansed) this will stop and you will give birth to a nasty little slime-baby. This thing will follow you about (you have a huge amount of threat on it and it's un-tauntable) with a damage AoE and spitting ooze about the place. Nasty.
As soon as you get the infection you need to run out to a tank patrolling the edge of the room, there are three things you might find when you get there:
- Just the tank - when your slime spawns you need to just hang out with the tank for a bit (don't bother with conversation), move where they move because you want them nearby soon and they are probably keeping an eye on where ooze is spawning.
- The tank and another raider with a little oozeling - in this case you want to get your two oozes to join. They love to do this so you should only need to keep them together for a little bit. DO NOT leave the area until they join though, else your slime will come with you and spit on the raid group.
- The tank and a big ooze - The big ooze is the product of two or more little oozes joining. When it spawns it can (and should) be picked up by the tank and kited around the room you need to run just in front of the big thing and drop your ooze so that as soon as it spawns it's climbing inside the big one.
Once your slime thing has been dealt with you need to get back into place and DPSing the boss. Again, Circle
is great for this -- remember that you will also be turned to face the same direction as when you lay down the Circle so you can get right back into the groove very quickly, just never do it while you still have a slime devotee.
The big ooze shouldn't cause you any trouble but when it gets too big it does explode, shooting out several little slime projectiles
. These hurt a lot and do splash damage, so once they have been launched you need to relocate till they land (they target where people are stood so they don't adjust aim in mid air). They don't leave any nasty residue so get right back to the DPS.
That's it, fun, frantic and frankly, if you can keep a straight face during the ooze explosion you're a more stoic warlock than I.