Positioning

In this phase the Lich King, (i'm just gonna type Arthas from now on cause it's easier) can basically be tanked anywhere. However, if you keep closer to the edges, it will make phase transitions easier.

Make 3 piles, triangle formations. One will be your melee, were your tank and Arthas are. One will be your ranged, all of them. Healers can go on either pile I suppose. And your last pile will be your OT, all by himself.

More will be explained later on why these piles, they have to do with Necrotic Plague and the adds, in which your OT would be tanking.

Infest

Every 25 seconds or so, with a 2 second cast, he'll do this on the entire raid. What it does is do a raid wide 10K shadow damage, though some of you can LoS it. And it leaves a DoT, doing 1K damage per 2 sec, but increases in damage by 10% per tick. So think like Curse of Agony.

The only way to remove the DoT, is to heal the person up to above 90% hp. So think like remember all those Bleed DoTs that don't go away until you heal the tank to full health. Like that, but raid wide, increasing damage, and only 90% hp.

This would be your raid healing check.

Necrotic Plague and Plague Siphon

He'll cast this on a non-MT. A 50K dot so yea you're dead. Or not, it takes 5 seconds for the first tick to happen, you have to cleanse it off before that happens. Either way, it will not go away but instead jump to another nearby, and Arthas increases damage via Plague Siphon, 2% more physical damage per stack.

If you die to it, the plague will gain a stack and jump to someone nearby. This gets stronger and stronger, 100K, 150K, etc. You still have 5 seconds before the first tick.

If you cleanse it, the plague will lose a stack, but still jump to someone else. Again you have 5 seconds before cleansing it.

The final trick to this plague is that it can jump to the adds that Arthas summons. If utilized correctly, this would be a very significant help in dps'ing them down. Think of a 500K DoT jumping between those.

With the above positioning, you should already be in your stacks, triangle formation. The person that gets the plague should make a run for the OT, where the adds should be tanked. Cleansers, should not insta-cleanse. Wait maybe 3-4 seconds and hit it, and hopefully, the Plagued Person reacted fast enough earlier to make it all the way to the OT and it jumps into that pile. If not, then the next person that it jumps to must attempt the same.

Due to the Plague Siphon, the jumps must be kept to a minimum. The way you'd control it is to stagger those cleanses, wait the 3-4 seconds. And then hope it'd jump on to the adds where they'd have the hp to last a while with the DoT on them. Remember at 50K you guys probably won't last a tick, but they'd last a few, and killing them in the process

Shambling Horrors and Dredge Ghouls

The adds. First I'll mention the Dredge Ghouls, every 25 sec or so, Arthas will summon them. They're basically the "little ones" that you can just kill with splash aoe. Just aoe splash/tank them down. Both tanks can pick up whatever they can that happen to spawn nearby. Though Arthas might move a bit if MT picks up too many. So OT should taunt off if need be.

Next up is the Shambling Horror, summoned every minute or so. They're the big ones that must be OT'd. Back to triangle formation of the above, the OT tanks it by himself off to the side away from the melee and ranged piles.

This is where the above Plague dance would come into play. You'd attempt to get the Plague onto the adds and use that to kill them. All the while you'd focus down Arthas himself. Repeat until 70% and finish off remaining adds during transition. There should not be many up if done fast enough, or at least they'd be a low health to pick off quickly.

Note: The plague jump appears to be a 10 yard range. If this is still jumping in this phase, make sure the person is far away when cleansed. For example, you can keep the melee away from the Ghouls/Horrors at all times, let ranged and plague kill them. Then cleanse it off your OT, it should disappear.

Remorseless WInter

Arthas will run into the center of the room and start channeling this, dealing 10K Frost damage per sec (7K in 10 man) to anyone within 45 yards. So the raid must run out to the edges of the room.

The first transition phase will be easy. Simply make sure you're on the outer rim before or at 70% when he runs to the center.

The second transition is a bit more tricky due to the outer rim not being there. It does respawn, but after he casts this. So you'll likely have to take a tick or 2 before getting on the platform. Just don't go too early and fall to your death.

Pain and Suffering

In the meantime will just chain cast this spell. It's a frontal cone 5K ish (3K in 10 man) shadow damage leaving a 800 per sec DoT for 3 sec (500 in 10 man), stacks to 5.

Think of this like the Vashj lightning in her Phase 2. He'll just randomly fire it off from where he's standing in the center. The raid should try to spread out so hopefully, you're not continually hit by this. Less raid damage is always better if possible.

Ice Spheres

These are summoned the entire phase and locks on to a target with a blue beam, Ice Pulse. Also, anyone within 5 yards of the target will be hit by an 5K (3K) aoe. So spread away from that person to minimize raid damage.

The spheres will move slowly towards its target. The ranged is to kill those before it reaches it. So, say similar mechanic to Putricide oozes. If it reaches its target, it will do Ice Burst, a 10K exploding knockback. Which is, bad.

Raging Spirits

They are shadow clones of the raid. With more HP, and able to do a frontal cone Soul Shriek, 30K shadow damage and 5 second silence.

There'll be 3 of these, they are tankable and should be divided up among your tanks. So, don't stack, keep spreading out as much as possible, face away from raid. Kill them.

Quake

At the end of this phase (60 sec) Arthas will destroy the other rim with this move. You'll see the floor light up with blue crack lines, so just move back in before you die. Drag any Raging Souls left, leaving them to fall will evade bug and teleport return with full health or some other bug. Ice Spheres should be avoided and killed asap, they still explode and do the knockback if up.

Soul Reaper

This is what Arthas will start doing on the MT. It'll be an initial hit of 100% weapon damage as Shadowstrike Damage. Also leaving a debuff, in which after 5 seconds it ticks for 50,000 shadowstrike damage again. Shadowstrike would be a shadow/physical combo. What you'd be hit with is what you're more vulnerable.

Both applications are resistible, absorbable, mitigatable by about everything. Though the initial hit appears to be more partially resistable than the debuff. Also after the debuff ticks, Arthas will gain 100% haste for about 7 seconds. CDs, and some more heals will be needed to get your tank through these. Though, not necessarily the heavy external CDs, the small short ones that you can alternate are sufficient.

• Death Knights - Vampiric Blood, 4pc T10, Icebound Fortitude, etc
• Druids - Barkskin and 4pc T10
• Paladin - Ardent Defender, the big hit will likely take you below 35% hp, so automatically reduced by 20%, if not, then you didn't need the CD in the first place.
• Warriors - Shield Wall, Last Stand, 4pc T10

Defile

Every 30 sec or so, he's cast this randomly on anyone in the raid (tanks too). It places a puddle of black (void zone) underneath you that hurts, and lasts for 60 seconds.

Not only does it hurt, but for each tick anyone takes standing in it, it will grow. And will grow quite fast. Very fast. Which can become a problem in a not so large room with other mechanics going on.

So, run out asap. Perhaps coordinate to have your people run North/South while the raid runs in the other direction. Do not ever run through them for any reason what so ever. Do not touch these for any reason. Do not pass go.

Val'kyr Shadowguard

Every 45 sec or so, Arthas will summon a Val'kyr. What she'll do is randomly chose a raid member and grab them. Then slowly fly to the edge and chuck them off. Yes you read this right.

The DPS are to switch and kill her before that happens of course. She's snarable, but only up to 50% speed reduction. She is also stunnable so use those to buy time.

Ranged DPS will be best for this due to possible Defile in her path. But melee dps will be needed to help, just be careful around Defiles, and around the Defile CD timer. It could occur at the same time Valks are summoned which could mess things up.

That's the big thing of this phase, dealing with the Val'kyr and Defile mechanics together. You likely might want to spread out or prepare to during Defile CDs regardless of Val'kyr. Perhaps just send one person to Valk during that time to stun/snare it and wait for Defile to be dropped first.

Harvest Soul

Every 75 sec or so, Arthas will channel this DoT on someone in the raid. You heal them through it,. Because if they live, they get phased out. There'd be another room "Frostmourne", you get to hang out with Terenas' ghost as he battles with a Spirit Warden, think Kalecgos style

Frostmourne Room

In here, you'll get a damage buff, Harvested Soul, allowing you to do 100% more damage. For the DPS classes, the Spirit Warden will go down fairly fast. For the healers, Terenas will do more damage the more health he has, so spamming into him is your key to getting it done asap.

Soul Rip is the only other thing to be aware of in this phase. It's a channeled cast the Spirit Warden does, that puts a stacking shadow damage debuff on Terenas. Left alone, can potentially kill him, maybe. At the very least it'll slow down your progress in the room.

So if you can interrupt, interrupt. Stuns work too if you have those instead. A magic dispeller also works to get it off Terenas. Every class should have some sort of options to deal with this. Otherwise you'd have to hope you can dps it down on your own fast enough or heal through the stacking damage. But again, every class should have an option to do a single interrupt/stun/dispel to pass this check.

After Spirit Warden is killed, Terenas will resurrect you back into the fight. It is in your best interest to get out of this room asap since they'd be 9 manning it on top.

Vile Spirits

The final trick of the phase is summoning of Vile Spirits, 10 in 25, 8 in 10 man. They will start above up and will just float there for 30 sec or so. After which, they will head towards the raid and explode for 15-20K damage, each, to all within 5 yards of them.

So the ranged has to try to kill as much of them as possible while they're in the air. Once they become active, continue try to kill them while kiting. They are susceptible to CC / snares / stuns.

The melee can never directly touch them without risking it exploding in their faces. So they must run away if a Vile Spirit is near should they be able to do nothing else. It is quite better to avoid unnecessary damage in this phase than to blindly turret. In other words, don't be stupid, you should have plenty of time in this phase.

Ooze Flood

First thing of note is the room. Every so often, an entire quadrant will be flooded with ooze, which of course hurts you and snares you.

Ooze will start flowing from the pipes there first before the flood, so can watch for that and get out of there. The 4 quadrants will be randomly filled, but each one must be filled at least once before re-randomizing.

So, the tank should tank Rotface in the center, the ooze won't reach the inner inner circle of the room. The raid can all stack up there too, in normal mode at least.

Slime Spray

The first major ability Rotface does is Slime Spray. This is where he randomly turns towards a raid member, starts a cast, then channels a frontal cone attack damaging all in its path.

The raid just has to move away from where he's facing to avoid as much of that extra unnecessary damage as possible. This is where stacking in the center for normal modes would benefit too, less distance to run if you can all just go through him to the other side.

Mutated Infection

This would be another major mechanic. What it does is puts a DoT on you, and the debuff also serves as a Mortal Strike effect. When it expires, or cleansed, it will spawn a small ooze which will be attacking you.

Little Ooze

Spawns when Mutated Infection is cleansed, and will be attacking you and spewing out a small damage aura. Let it, it won't hit that much, and has an immense threat lead so it won't go away until you die, or do some total aggro drop.

When 2 of the Little Oozes get together, they will merge to form a Big Ooze. Your goal is to take that ooze out of the raid so they do that.

Big Ooze

When 2 small oozes come together, they'll merge into a big one. These guys operate on a normal threat table and can be tanked, though shouldn't. They will hit very hard and should be kited around the room.

Can be kited by any class that can kite, hunters, locks, mages, etc. But likely, you'd want to stick with a tank class for that extra damage / hp buffer. Do ranged threat moves when possible, so obviously, some tanks are better than others for this task.

Meanwhile, people with the Little Ooze should drop theirs near the Big one so they merge with it. With each one merged, the Big Ooze gains a stacking buff that increases their damage by 20%. All the more reason to kite it around, and stay away due to the aura it has too.

Unstable Ooze Explosion

At 5 stacks (oozes merged), the Big Ooze will stop and do a cast and then explode. Sending 8-10 ooze missiles into the air in which they will land where the players are doing a lot of damage.

So the raid is to watch for that and move, it's like a Shadow Crash, it'll hit the location you were at when targeted. So if the raid was mostly all in the center, that's where all the missiles will hit, get out of there.

And that's basically the cycle of the whole fight. Avoid slime spray, get Mutated Infection, take the little oozes out to big ooze, kite the big ooze, avoid the explosion, repeat til dead. Except, the rate of Mutated Infection will increase as the fight goes along, so things can get hectic at the end.

Hard Mode Summary:

More damage, more HP, and Professor Putricide joins the fight from the balcony performing...

Vile Gas: This is similar to the Festergut one, but not as lethal. What it does is roots you for a second or two, you can still cast it and all. And it still hurts people around you. The adjustment the raid has to make is to keep the minimum amount of ranged at ranged (3 / 7) and spread out so it's not cast on the melee pile.

Otherwise it's the same fight, this is a relatively easy Hard Mode, comparatively.