Yor'sahj the Unsleeping
When you first start the encounter, and before the summoned globules reach Yor'sahj, the encounter is more or less a tank and spank. His Void Bolt will hit his primary target for shadow damage, placing a damage over time effect that deals increasing damage for each stack of the ability every 2 seconds. That's right, the damage stacks -- but at the very least, it stays to tanks. If you are assigned to tank healing, make sure you're keeping Earth Shield on the tank, and it's a great time to break out the Greater Healing Wave to make sure the tank stays alive. You can also position Healing Rain so that it can sit not only on the tank but also catch your melee. Overall, this phase isn't too bad; like I said, it's mostly a tank and spank.
About every 80 seconds, the boss will cast Call Blood of Shu'ma where the boss will head to the center of the room and begin summoning the various slimes that you have to contend with in the next phase. All said and done, it takes about 20 seconds for the slimes to reach him; this phase is what I consider the down phase or regen phase for you. Getting those Lightning Bolts cast to take advantage of Telluric Currents is a smart idea here. It's even a great time to use Mana Tide Totem if you need to. Trust me, you'll need the mana for the second phase. When the oozes hit the boss, phase 2 begins and the entire raid should be grouped up to handle the incoming damage.
Know your ooze
Don't try to remember all of the proper names for the various oozes. Most people (and in fact, most boss mods) will simply just refer to them by their color, which is exactly what we're going to do here today.
Glowing Globule, or the yellow ooze, has the special ability of Glowing Blood of Shu'ma, which allows Yor'sahj's void bolts to hit every single person in the raid. If that wasn't enough, he will also cast them twice as often. The good news though is that this version of it doesn't have the DoT effect that the original version of it has. The increased damage usually is a cause for yellow to be a priority kill for most groups, but it's nothing you can't heal through. Our mastery, Deep Healing, is especially handy when this is active.
Cobalt Globule, or the blue ooze, has the special ability Cobalt Blood of Shu'ma, which gives Yor'sahj the ability to summon Mana Void. When the mana void comes out, it will drain all of the mana from every caster in the raid. You can use mana gains for temporary mana back, but while the void is active, you'll be at zero until the mana void is killed and Mana Diffusion covers the raid. In normal modes, it will give you mana back if you're within 30 yards of the boss; in the Raid Finder tool, that is increased to 100 yards.
Crimson Globule, or the red ooze, has the ability Searing Blood which deals damage to a number of targets in the raid group. This will be three people in the Raid Finder and 10-man normal, and eight people in 25-man normal. The trick here is that the damage increases the further away the targets are from the boss. When this ooze is active make sure that everyone is grouped up on top of the boss so that the damage is actually healable.
Dark Globule, or the black ooze, allows Yor'sahj to summon a small army of Forgotten Ones. They will fixate on a target and will cast Psychic Slice, dealing damage to their target. It has a 5-second cooldown, but it will add up. Even after your raid group kills off the adds attacking your raid, the boss will continue to summon the adds until the phase is over, so be mindful.
Acidic Globule, or the green ooze, will enable the ability Digestive Acid. It's a disgusting ability that will cause the boss to through out acid blobs that, when they hit the targets, will cause splash damage to anyone within 4 yards of the target. In Raid Finder modes, the acid does not have a splash effect, but in the normal modes, it's something you need to be concerned about. The good news is that the spread out distance is only 4 yards, so your group healing will still be effective here.
Shadowed Globule, or the purple ooze, brings the ability Deep Corruption into play. To be honest, this ability is a healer's nightmare. After every healing or absorption effect, players gain a stacking debuff. When that debuff hits five stacks, it explodes, dealing massive AoE damage to the raid. This makes healing very dangerous and something you'll have to watch out for. If you have Grid or any other healing raid frame mod that allows you to track debuffs, this would be a perfect time to enable it.
Mix and match your oozes
Individually, the oozes aren't that bad and can easily be handled, but when you combine them together, things can get quite sticky. First and foremost, during the group-up phases, make sure that your Healing Rain is down, keep Healing Stream Totem active, and roll your Chain Heals. In most combinations, that will see you through the worst of it. But some combinations of oozes will have some very interesting and potentially disastrous effects.
Red ooze with green ooze can be very difficult to heal through, considering that you'll have to spread out and group up at the same time. Let's face it, that's pretty much an impossibility. It's regarded as the hardest combination for healers to get through. If you do get this combo, emphasize that your raid use personal survival coolodwns, and heal your heart out. The same goes for yellow and green, for the same reason. While it's slightly easier to handle than redand green, it still hits hard. Purple oozes should never be active when a yellow or red is up, so no matter what, the damage will be healable; you'll just have to keep on your toes. Keep Spirit Link Totem handy for when healing gets especially dicey, like a yellow/black combo, and keep pushing out the healing. It's a fun encounter and will definitely give your healing fingers a workout, so be ready.
The boss does have quite a bit of very nice loot to hand over when you've taken him out, quite the rewards for your time and effort.
This boss is a bit of a workout for healers, but he's not the hardest healing encounter in the zone. The entire encounter does play well with our abilities as restoration shaman. It's a great opportunity for us to shine and get some pretty good loot out of the deal while having some healing fun.
Totem Talk: Restoration lets you Ask a Shaman about the tricks of the trade. We'll introduce you to the very latest pre-raid gear and show you how to manage your cooldowns. Happy healing, and may your mana be plentiful!