Only two bosses stand between you and victory in Ulduar. General Vezax, leader of the Faceless Ones, guards the entrance to Ulduar's final chamber. Inside that room, we find Yogg-Saron, the Old God, who's powerful influence captured the Titan's minds and ensnared the denizens of Ulduar. With Yogg-Saron out of the picture, perhaps you will be able to clear the corruption from Northrend.
While not quite the technical challenge that is Mimiron, these two bosses are the strongest two enemies you'll encounter in Ulduar. More importantly, each fight has very specific roles that a Rogue will need to play in order for the raid to succeed. After the cut, we'll explore exactly what you'll be responsible for as you descend into madness.
First of all, the General is incredibly creepy looking. I wouldn't want to run into him in a dark sewer tunnel underneath Dalaran. He's the leader of the ancient Faceless Ones, who we learn are serving Yogg-Saron. Vezax is the gatekeeper to Yogg-Saron: we have to kill him in order to engage the Old God. Luckily for us, Vezax is fairly simple for Rogues, provided you know how to maintain a Kick rotation.
Vezax becomes a tank and spank for Rogues, with no notable abilities we have to avoid or watch out for. He does have an aura which reduces our attack speed by 20%, but this is offset by how simple the fight is for Rogues. Casters will have to constantly be avoiding AoE attacks, debuffs, etc; Rogues get to sit on the boss and take him down.
However, Rogues are also assigned a very important role in this fight: Interrupting Searing Flames. This is by far the most important job a Rogue will get in Ulduar, next to interrupting Stormcaller Brundir. Searing Flames will deal massive raid damage to everyone, and will reduce your tank's armor by 75%. Vezax is already one of the harder hitting bosses in the instance, your tanks will die if they get hit by the Searing Flames debuff. Your #1 priority must always be interrupting Searing Flames, at ANY cost of personal DPS.
In order to assist you with interrupting this cast, you will have another Rogue (or interrupting class) assisting you with this job. I highly suggest you both get Deadened (mentioned in last week's ET) to notify each other upon successful and failed interrupts. It's far easier than typing it out, and allows you to keep Vent clear for the fight. Communication is key: if you both blow your Kick cooldown at the same time, neither of you will have it available for the next cast.
Some of the commenters last week mentioned using Deadly Throw / Fan of Knives as a 'backup' interrupt via Throwing Specialization. If you're combat, I would suggest putting points into this talent as purely a reserve option in case of emergency. My other suggestion is to swap in a pair of PvP gloves for this fight. Depending on your raid's DPS, you will be interrupting between 10-20 times during this fight. Assuming 15 interrupts, wearing the PvP gloves now gives you as much energy as a 2nd Adrenaline Rush over the course of the encounter.
That's not even including the fact that with Kicks only costing 15 energy, it becomes crazy easy to maintain as Kick is also off the GCD. In addition, the higher end PvP gloves actually have reasonable DPS stats on them as well. It's up to you to choose, and this advice will vary based on your set bonuses and gearing choices.
DPS the boss, Kick Searing Flames, collect loot. That's about all you'll be doing on this fight, so enjoy one of the easier bosses you'll personally face in Ulduar. You deserve it after Mimiron's sadistic robots.
A fight in 3 phases, you'll see yourself doing many different things here, depending on where your raid leader wants you. Luckily, our job is simply to DPS whatever we're told to, and this means we're able to focus on positioning and our rotations. The fight only has one real catch: you're struggling to not going insane. Yogg-Saron gives everyone in the raid a Sanity debuff, with 100 charges. Once all 100 charges disappear, you'll become Mind Controlled, and be completely unable to recover from it. I'll go over the specific ways you'll be losing (and regaining) Sanity, but be sure to keep the idea in the forefront of your mind during this encounter.
Phase 1 is fairly straightforward, you'll be killing adds (Guardians of Yogg-Saron) near the floating Sara. They explode upon death, and will help you in killing the "friendly" Sara. Think of these like the Lasher packs of Freya. Be sure to use Feint to reduce the incoming damage you take upon explosion, and assist with interrupting Dark Volley if you're nearby. Also, I shouldn't have to mention this, but please stay out of the green clouds on the ground. These spawn extra adds, and can easily overwhelm your group.
So you've killed enough adds to bring Sara to 0 HP, and now we're moving to Phase 2. Here's where your role will vary greatly, based on which group you're assigned to. The raid is split into two pieces: one for tentacles up top, one for the tentacles and brain below. I'll discuss each portion separately, but make sure to know which job you're performing before the pull.
The topside group is responsible for killing 3 types of tentacles as quickly as possible. There's one tentacle you don't want to touch (Crusher Tentacle – think Snaplasher in Freya or Bomb Bot in Mimiron P3), one you want to focus on (Constrictor Tentacles – think Kologarn's Right Arm or Ignis' Slag Pot), and one you only kill when you've got spare time (Corruptor Tentacles – think of the Junk Bots on Mimiron P3). Ranged DPS will handle the Crusher Tentacle, as it will destroy any melee in range and the tank will be dipping in and out of range of the tentacle to avoid getting gibbed.
Melee's #1 priority is to kill Constrictor Tentacles as quickly as possible. These will pick up and choke a raid member, and so destroying these tentacles will free the raid member and allow you to move on to your next objective. You'll be spending the majority of your time in P2 killing these tentacles. If you happen to have all Constrictors taken care of, focus on killing off a Corruptor Tentacle or two. Most of the Corruptor damage can be dispelled, and so destroying them is 2nd priority behind Constrictors. If you're getting hit by a lot of the Corruptor DoTs and debuffs, cloak 'em!
While up top, you'll be attacked by Sara as well. She has a few moves you'll want to watch out for. Brain Link will link you with another raid member, and will reduce your life and sanity if you're 20 yards away from each other (Wedlock, anyone?). Just huddle up with the other person until the debuff fades. She'll also cast Death Ray, which is yet another laser you'll want to run away from. Finally, she'll cast Malady of the Mind, which causes the target to spread the disease after a few seconds. If you see someone with MotM, run away!
The portal group will be assisting the topside group for portions of the fight, but will depart from the raid group and enter into Yogg-Saron's insides to kill his brain, once the portals have spawned. You'll want to get into the portals as quickly as possible, and make sure you have a speed enchant or talent for this phase. Once inside the portals, you'll be confronted with Tentacles and crazy skulls. Your job is to avoid facing the skulls, and to kill the Tentacles: in that order. If you are facing the skulls, you take damage and lose Sanity at alarming rates. You'll need to strafe around inside the portals, ensuring your back is ALWAYS facing these skulls.
Once you've got your back to them, you work on killing the tentacles inside. Once finished, you'll get a shot at attacking Yogg-Saron's brain. Unload DPS into it: once it reaches 30% the fight will transition into Phase 3. Now, you only have 60 seconds total from entering the portal until Yogg-Saron casts a spell which will instantly remove 100 Sanity from you. So, killing Tentacles and quickly moving to Yogg's brain is key, while also giving yourself enough time to run back to the portal before your 60 seconds are up. While you're back topside, waiting for portals to respawn, attack the tentacles and refill your Sanity meter by standing in one of Freya's Sanity Well (big green beams). If your raid has good DPS, you'll be able to minimize the number of portal phases you have to endure.
Phase 3 brings back memories of Vaelastrasz in Blackwing Lair, where the boss starts at 30% and is pretty much a field day for anyone with an Execute-style move or talent. The one catch to this phase is that Yogg-Saron will summon Immortal Guardians, whose damage is directly based on their current HP. This means that quick DPS is needed on new spawns to reduce the incoming damage your tanks will be feeling. Once they are brought low (1-2%), Thorim will shock them with lightning, killing them. It's important that they are brought low and also kept low, as Yogg-Saron will try to heal them until Thorim finishes them off.
Yogg-Saron also picks up the ability used by the skulls inside of his head: Lunatic Gaze. You'll want to immediately face away from Yogg when he casts this ability, and face back once finished. This phase is all about the balance between add DPS and boss DPS, as you need to focus enough DPS on Yogg to destroy him before he enrages, while also keeping the adds low enough that Thorim can eliminate them. Rogues are typically assigned to kill the Immortals, as our Execution-style abilities are lacking, and we're also capable of using Wound Poison on the Immortals to reduce the incoming healing. Focus on whatever your raid leader instructs you to, and if your group can keep up with the enrage timer, you'll be collecting your loot in just a few more minutes.
Obviously, you can see that the final fight of Ulduar is among the most complex we've seen in the past few years. Yogg-Saron takes most guilds several attempts to learn, so prepare yourself as best you can, but realize that nobody has ever 1-shot this boss. There's a lot of pieces to learn, and as your entire raid becomes more experienced, each piece will become easier to perform. Best of luck!