Ok even though ICC has been out for months and there are countless resources online that teach how to do all the fights and different strategies for them, there are still COUNTLESS players that fail terribly at every fight. 
This guide aims to address all the most common mistakes of every encounter, in order to improve the quality of our PuG population. 
If you're an exasperated Raidleader with some scrubs you can't kick, maybe directing them here will be good.
Who knows, this can be the place PuG makers direct their raid to "ok before we start, go read ... "

I'll not be doing a comprehensive cover of the whole fight, just a brief summarizing statement of the fight with the common mistakes listed. If you're an average player just needing good tactics for every fight, you should refer to stratfu or other resources. If you are some pro, maybe my HM guide can assist you even if in a small way. http://www.mmo-champion.com/raids-du...l-mode-bosses/

This is for the bads.

Don't be ashamed of not knowing any of this, we all start somewhere. 

Lord Marrowgar
What? Tanks stack up, Raid stacks up, dodge flames, dps boss, dps spikes when they come up, run away
and spread out for bonestorm. Rinse and repeat. Collect loot.

Noob mistake #1 - Not stacking up for normal phase.
If you're not a hunter, you should be standing where all the melee are standing. If you have boss selected you should see a red circle that highlights him on the ground. You should be INSIDE the back half of that red circle. 
Being a huntard doesn't give you the excuse to stand 21307 yards away though. Stand as close as you can.

Noob mistake #2 - Not DPSing Bone Spikes
I know you're trying to top DPS charts so you can boast about how leet you are. BUT YOU NEED TO KILL THOSE BONE SPIKES. If everyone follows #1, all you need to do is press Tab and you'll switch target to the closest bone spike. DPS down. them all. If there's a spike in range you'll have to turn and target it. How about this, top DPS for damage done on bone spikes, and boast about THAT to your raid. See if you still get those 'tunneling scrub' insults you always get.

Noob mistake #3 - Moving in front of the tank after Bonestorm
I know it's messy, I know you're panicking, but if your raid is like 99% of the raids i've seen, the tanks will be marked. STAY AWAY FROM THEM. Make sure you don't walk between them and the boss, since the boss has a pretty large cleave. 

Pro tip you never knew - Boss doesn't move to same spot twice for Bonestorm (i.e. doesn't target the same 
spot twice.) That's a safe zone for you.


Lady Deathwhisper
What? DPS boss' mana shield down, kill adds when they come up, back to mana shield. Time breaking of shield
to be well before adds spawn. After that, rotate tanks at 3-5 stacks, dodge ghosts, watch threat.

Noob mistake #1 - 100% DPSing the boss
See those monsters that come out from the walls? Hint: DPS them instead

Noob mistake #2 - DPSing the wrong type of add
If you're a caster, DPS Cult Fanatics first (the melee ones). If you're a melee/hunter, DPS Cult Adherents first (the caster ones). If there's an Empowered/Reanimated add, that takes priority over normal ones.

Noob mistake #3 - Dying to exploding spirits in Phase 2
Those swirly white things that come out from the boss are not powerups. They hurt. Move from them. You need to move from them BEFORE they start chasing you (if they're within about 10 yards of you even if you run they'll stil explode and damage you)
Tip- look at your portrait, if it turns red (pull aggro) means a ghost is after you.
Green stuff on the ground hurt too. Get out of them.

Noob mistake #4 - Pulling aggro in P2
I know you're winning with 2 buttons, or your DoTs can't stop ticking. Guess what, Invisibility /Soul Shatter helps. Asking for a Salv works too. Or, you can just stop casting. LDW has been nerfed so much enrage really isn't that much of an issue anymore.

Pro tip you never knew - Left side adds are ALWAYS 2 melee, 1 caster, and Right side adds are ALWAYS
2 casters, 1 melee. 25man Raid leaders may want to have this in mind when assigning sides to groups to
ensure a proportionate divide of casters/melee on the sides.


Funship
What? Press 1 and 2 in cannons, shoot some adds, jump over to kill some mage when your cannons get frozen,
jump back when she's dead. rinse and repeat.

Noob mistake #1 - Those big orange circles that appear on the floor hurt. Don't stand in them. No, you can't play a racing game on normal mode with them, they don't knock back.

Noob mistake #2 - Shooting the ship ONLY instead of shooting the adds in cannon.
When there are things alive, you should kill them. I've seen people shoot the bottom of the ship for god knows what reason. Angle your cannon towards the deck of their ship, and shoot. If you don't see many numbers, you're aiming wrong.

Pro tip you never knew - You can jump off the ship once combat starts, but not before. It teleports you right back. 
ok sorry it's hard to think of something someone never knew for this.


Deathbringer Saurfang
What? Burn that fat test dummy, when little red creatures spawn kill them first, then switch back to boss.
Heal up those that get motfc, etcetc.

Noob mistake #1 - 100% DPS on boss and not switching to Blood Beasts
Things that crawl towards you need to be killed. Fast. Don't tunnel vision, kill Blood Beasts whenever they
spawn. Don't think you're spared from this as melee - you can do something useful like stunning an add as it gets
close to range, etc, if your ranged DPS can't handle it.

Noob mistake #2 - Melee DPs/Tank AOEing and hence pulling aggro of Blood Beasts
Watch your timers, don't AoE when Beasts spawn.

Noob mistake #3 - Incorrect usage of snares such as Frost trap, earthbind, typhoon, thunderstorm
For ANY immobilizing snares, do NOT do it when the adds are still in melee range (i.e. Frost nova, Entangling Roots) since they will attack the nearest melee target. Things like Shadowfury/Stuns dont matter since the adds are, well, stunned.
Frost trap needs to hit as many of the beasts as possible, and if it's the only snare the group has, it needs to hit the beasts BEFORE they start moving. I've seen hunters place the trap at the bottom of stairs so the beasts get a good 10 yards of normal movement speed before being slowed.
Earthbind (the elemental shaman's improved one) should not be dropped just as adds spawned since this will make the first tick root them right next to the melee, leading to the first problem mentioned. Unless it is your only raid snare, you should be using it as an emergency (e.g. adds getting close, drop earthbind to root them) if thunderstorm is on CD
Thunderstorm / Typhoon should be used AFTER whatever stuns you have, and not before the adds start moving. The reason being if you knock them back IMMEDIATELY when they spawn, you lose some DPS due to out of range issues (they take about 1-2s to start moving, that's easily 1-2 spells)
It's best to save thunderstorm for emergency uses too, Typhoon is better for the inital knockback.

Noob mistake #4 - Standing too close to other people / Getting hit by adds / Falling asleep for Rune of Blood / Other things that make boss gain BP faster.
SPREAD OUT. There's plenty of room, even for 25man. Just type a /range 10 (exact range of Boiling Blood is either 9 or 11 i can't remember) and yell at whoever's too close to you.
Don't get hit by adds. Use Blink/Disengage/Fade/Thunderstorm/DemonPortal (have i covered all range classes?) If the add still has half HP and is about to touch you, there's something wrong with your other DPSers. Most likely a problem with mistake #1. Tell them to wake the f--- up or Misdirect a beast to them the next time.
Don't miss taunts please. As a tank all you have to do is press Taunt when Rune of Blood is placed on the other tank. And watch your AoE. and gain threat. I don't think the last 2 are hard, and i still see tanks miss taunts. I'm not even talking about ability wise missing, i'm talking about brain-wise.

Pro tips you never knew - Disc shields are excellent for Boiling Blood, slowing BP gained by Saurfang.
Btw, Bloodlust is used when Saurfang uses Frenzy (when he hits 30%), not anytime else. (i've seen RL ask for it at random times like at the start.. after first Mark.. after first blood beasts..)


Rotface
What? Shoot boss, dodge slime spray, run to the offtank when you get the debuff, move out of centre when explosion happens. rinse and repeat.

Noob mistake #1 - Not moving out when you get Mutated Infection
STOP TUNNEL VISIONing!! Well firstly make sure you have some up-to-date boss mods installed that warns you in big flashing text or vibrating screen or picture of a hot girl or whatever is required to jolt your attention when you get the debuff.
When you get Mutated Infecction, MOVE OUT OF THE RAID. If you have no idea where the offtank is, move out of the raid FIRST, then start looking for him.

Noob mistake #2 - Dying to Slime Spray
When the boss turns to face you.. MOVE AWAY. Strafe to the side or something. It's pretty obvious where he's aiming his Slime Spray by the direction he is facing, and his hands start spasming.

Noob mistake #3 - Running to Big Ooze instead of in front of it
The reason why you should not be running directly to the Big Ooze is because
1) It does AoE damage , 2) It moves.
If you move to it directly, it's going to be moving forward towards your OT, so you'll need to trail it to let your little ooze merge with it, and hence take unnecessary damage from Big Ooze.
The correct way is to stand in front of the Big Ooze's path, behind your OT.

Noob mistake #4 - Running out too early for Unstable Ooze Explosion
For DBM, there are 2 warnings - 'Big Ooze is casting Unstable Ooze Explosion', and then some flashing blue warning that tells you to move.
You should only be moving at the 2nd warning.
The cast time of the explosion is about 3 seconds, so the first warning simply tells you when it STARTS casting. The impact point of its flying goos is chosen when the cast is complete.
Thus if you move early it's pointless, the ooze will still hit you.

Pro tip you never knew - Several healers can stand with the tank instead of standing on the left/right leg behind Rotface. This reduces significantly the chance you'll get Slime Sprayed, so you can focus on healing more.

There are differing views about when Bloodlust should be used for this, though IMO it should be used at the start since there's the least movement. As the fight progresses the rate of Mutated Infection increases so people will be running around more.


Festergut
What? DPS check + tank/healer Cooldowns rotation test. Spread out in room, DPS boss, stack up in 3 groups for spores (2 in ranged 1 in melee/tank) Rinse and repeat.

Noob Mistake #1 - Screwing up spores. 
For 10, there needs to be one spore in melee, one in ranged. 25, it's 2 in ranged, 1 in melee. There are some other weird strats like 'discarding' one spore entirely but i won't discuss those.
Zoom your camera out to the maximum for this fight. You need to be able to see both ranged groups and melee.
if you see 2 spores in melee, one needs to go out, if you see 2/3 (for 10/25) spores in ranged, one needs to go in.
Remember to move 1-2 steps forward for the melee group so that the tank gets the buff!

Noob mistake #2 - Vomitting on everyone
Spread. the. f--k. out. Do a /range 8 or to be safe, a /range 10, and ensure that you're not near anyone else. 
For 25, only 3 people should get vomitted, for 10, it's 1. If there's any more than that, someone is standing too close to someone. 
It's most likely you.

Noob mistake #3 - OMG why does my tank keep dying?
You need to have some survival cooldowns for your tank when he has 2-3 stacks of debuff and boss has inhaled blight 3 times. 
Do some GS/Painsupp rotation on the tank. 
Tanks need to call out when they taunt too. I've seen so many tank deaths after a tank switch because the healers aren't aware that the tank has switched. If you don't have a mic, make a taunt macro that has /rw [yourname] TAUNTED!! and spam press it when you taunt.


Pro tip you never knew - You can use immunity effects to survive Pungent Blight Explosion and hence skip all the spores.
For example, as a mage you just DPS the boss without moving to stack for spores, and when pungent blight is cast, press Iceblock. 
- There needs to be 3 or 7 people MINIMUM (for 10 / 25 man) outside, at range from the boss, to prevent him for casting Vile Gas on the melee group.
If you are running with the minimum and someone dies, a healer who's stacking on the inside needs to quickly move out into range to maintain that minimum number.


Professor Putricide
What? DPS boss, switch to oozes when they spawn, rinse and repeat. Dodge stuff in phase 2. burn hard in p3.

Noob Mistake #1 - 100% DPS on boss, and screwing up transitions by not stopping DPS.
Same for any bosses with adds, adds are always priority. KILL THOSE OOZES WHEN THEY SPAWN. THEY HURT.
- Also, you need to STOP DPS on boss at 82%/37% respectively and wait for the next red/green slime to spawn.
I don't care if you think you can pop enough DPS to push it over, just wait for the next spawn. Enrage timer really isn't an issue now with the
damage buff. After all, you never know if you'll go 5 seconds without crits and then mess up the transition.

Noob Mistake #2 - Moving in too quickly to DPS Gas Cloud (Red ooze)
Melee DPS needs to wait till it has targetting someone before moving in. So hold your horses with those charge/sprints towards the ooze. It's not a footrace to the ooze. 

Noob Mistake #3 - Getting owned by Choking Gas bombs and Malleable Goo
Pro tip - if a Malleable Goo is aimed at YOU, you just have to run forward and it wont hit you. If a Goo is targetted NEAR you, LOOK FOR IT and strafe quickly opposite direction.
It is better to OVERSTRAFE than to move too little. That extra 1second of movement is going to save you 15seconds of DPS loss.
Pro Tip - Melee DPS need to DPS boss from the max hit box. This means to stand at the furthest possible distance and still be able to melee hit the boss. This will give you adequate time to react to Gas Bombs and dodge out of it. MainTank should move the boss off those Bombs ASAP.

Noob Mistake #4 - Kiting the boss too much in Phase 3, and hence running out of space fast.
This is probably the most uncorrected mistake I see for this encounter. Everyone knows the 1st 3 points, but noone seems to say much about this except for me.
I know as a tank, you're very eager for your chance to shine, and want to prove your pro kiting skills. Y'know what? You can go play Heigan in Naxx if you like kiting quicklky.
DON'T MOVE THE BOSS UNNECESSARILY.
The only times when you should be moving the boss is when Choking Gas Bombs is cast, and when you are going to get trapped by slime.
Don't keep inching step by step every second, it's extremely annoying and you'll keep making the DPS having to move for range.

Pro tips you never knew - 
- You can use Invisibility and Vanish (Immunity effects do not work) to dodge the stun from Tear Gas. For Invisibility, it needs to be cast within 1s of the boss starting his Tear Gas cast, otherwise you'll still get stunned. I'm not too sure about Vanish as i don't play a rogue.
- Taunt the boss from a range during the tank rotations for Phase 3. This allows your healers time to switch to you instead of having you instantly gibbed for a few ten thousands of damage.
- If there is no Slime puddle on the ground, the Abomination should attack the boss/adds as well for additional DPS. (even better, if boss is tanked near slime pools, you can do both at once)


Blood Prince Council
What? 3 different princes take turns to become more powerful. Spread out for lightning boss, run away from big fireballs for fire boss, keep the OT up for shadow boss.

Noob Mistake #1 - Running in the same direction, not spreading properly BEFORE Empowered Vortex
Preassign directions for melee DPS to run, and the rest of the raid should stay relatively spread out BEFORE vortex is even cast.
This way when it is cast, there is minimal movement, just the outer layer of people maybe spreading abit further outwards to prevent any accidental knockbacks.

Noob Mistake #2 - Dying to Empowered Conjure Flames due to poor kiting
The easiest way to handle this is to have the raid stand in a general centralized location such that the ranged/healers are around the same area.
When the fireball is cast, the person targetted just has to run backwards, and the fireball will pass by all the other raid members and have its damage minimized.

Noob Mistake #3 - Instagibs to Keleseth's tank / Pulling aggro of Keleseth
Whether it's an actual tank or a ranged DPS you're using to OT Keleseth, you need to ensure you have MINIMUM 3 orbs on you at ALL TIMES, best if you have 4 or 5.
It's a natural tendency to worry about threat on the boss, but that should really be your last concern. Priority is to get the 3 orbs FIRST, THEN build threat.
- That said, it is CRUCIAL to watch threat when attacking Keleseth, especially in the early stages. Heck, you can even not DPS Keleseth if you're afraid of pulling aggro.
There's no strict enrage timer, there's no rush. Just tell your raiders not to attack Keleseth if people keep pulling aggro.

Noob Mistake #4 - Kinetic bomb goes kaboom.
If you ever saw a lightning ball shoot at you and BAM you fly a mile away and drop to low health, it's most likely a Kinetic Bomb hitting the ground.
Whoever is on Kinetic bombs need to stay full time on them! Don't even bother DPSing the boss, especially when 2-3 bombs are up.
AFAIK, bombs are kept up by number of attacks; the magnitude of the attack does not matter. 

Noob Mistake #5 - Pulling Shadow Orbs off Keleseth Tank
Avoid using all types of AoE/bouncing attacks such as Chain Lightning, Starfall, etc for this fight. You don't want to make the OT's job even harder by gaining personal aggro on the orbs. Plus, the Orbs do have HP so will die over time if you damage them. So don't.

Pro Tip you never knew - A prot paladin tanking Keleseth is one of the ideal classes, since you can get a holydin to turn on RFury and heal to attract shadow orbs, then the prot pally just uses Righteous Defence to collect them


Blood Queen Lanathel
What? Get a bite order down, carry it out, run to middle for link, run to the side for shadows, spread out for air phase.

Noob Mistake #1 - Some noob shit getting the first bite instead of your top DPS
ALWAYS HAPPENS. Look, i know DPS charts matter alot for you to parse and try to fake your way into a trial at some top guild, but this is not the way to do it.
If you are not assigned to get the first bite (there should always be 2 ppl assigned to get it btw, as backup), DON'T DPS IN THE FIRST FIVE SECONDS.
This may seem crazy to some of you, but after seeing alot of "i was just doing white hits and 1-2 abilities!" "i only casted a few lightning bolts!", this is the best advice to give noobs.
Yes, don't even cast shit. You never know if you're going to get some huge awesome crits or something. Just WAIT for that 3-5 seconds, then start. 

Noob Mistake #2 - Blood link raping the raid
In case you didn't know, blood link doesn't just do damage to the 2/3 of you, but it also AOEs those around the blood linked targets.
The best way to handle it is simply RUN TO THE MIDDLE, and wait till ALL OF THE OTHER LINKED PEOPLE ARE STANDING ON YOU.
Make sure link is cleared before moving apart!!
Melee DPS need to be especially aware of this, since if you're dreaming and don't move out for blood link, you're going to kill the whole melee group.
SO. DON'T. DREAM.

Noob Mistake #3 - Deaths in air phase
Spots should be assigned - e.g. healers in middle, ranged at the sides, melee towards the wall/stairs, etc.
The best way is to actually start moving out to your position (i.e. further spread out) 3 seconds BEFORE Incite Terror is cast (should be before she starts running to the middle)
Try to have Tremor Totem in as many groups as possible, and once you found your spot, STAY in it. Don't be a noob and run around like a headless chicken. If your spot is in the middle but you get feared to the side - IT's FINE. As long as there's noone near you, you're fine.
Tip - Your first bite needs to be DELAYED, wait till the last 3 seconds before biting. (don't miss it though) This will prevent bites from having to go off DURING air phase. 
Subsequent bites should be ASAP.

Pro tip you never knew - Immunity effects like Iceblock/Divine Shield prevent you from splashing Bloodbolt Whirl onto a nearby target. This is not 100% confirmed but i've witnessed this a few times and it seems to be the case.


Valithria Dreamwalker
What? Kill adds in priority order, healers enter portal and win.

Noob Mistake #1 - Healers dropping stacks
You need to grab an orb within the last 10 seconds of leaving the portal phase, so time it as such. (it used to be 5, you noobs. already nerfed)
Enter portals ASAP. 

Noob Mistake #2 - Wrong kill order/prioritizing of adds
1) Blazing Skeleton. When it comes out, drop whatever you're doing, stop wanking, burst it down. Fast.
2) Suppressors. Many recommend to take these down immediately when they come out. Unless you're leet enough to notice whether portal healers are outside or inside (in which case other adds should be killed first), just kill these first. They don't have much HP anyway.
3) Blistering Zombie for ranged DPS, Archmages for melee DPS. This is the safest assignment to prevent melees from dying to the explosion of the zombies. 
4) Abominations - Remember you need to AOE down the worms after it dies. People always forget. A frost trap is extremely helpful here too.

Pro tip you never knew - Crusader Aura increases fly speed in the portal room. 
- Putting Beacon on VDW and healing a hunter's pet (specced Rhino [+40% healing]) which is next to VDW will maximise output. Note that beacon-transferred heals do NOT benefit from the 40% increased healing, but Glyph of Holy light heals do.


Sindragosa
What? Dont let your stacks go up too high. LoS bombs. Alternate tombs left and right and win.

Noob Mistake #1 - Failing at LoS
Although it wont kill you in normal mode, it's retarded to get hit by bombs. Just hug the Ice Tomb and make sure you're in a straight line to the blue circle that appears for Frost Bombs.

Noob Mistake #2 - Breaking Tombs too quickly (in whatever phase) 
For air phase, as a gauge, after the first bomb, tombs should be at 75%. After 2nd, 50%, after 3rd bomb, 25% (use this as a gauge if you're too fast. If you are going below 25% before the 3rd bomb, it's too fast)
For last phase, The existing tomb should be broken only when the next Frost Beacon target(not after the ice block forms, that may be a LITTLE too late) is in place (assuming he has normal reflexes and moves immediately to the spot)

Noob Mistake #3 - Failing to Blistering Cold
Don't stand too far from the boss, just at 30 yards or so for ranged/healers is enough.
The moment she sucks you and you're in the air, start turning your camera around. You should be facing your original position the moment you land and can start running.
Tip - If you have a good hunter in the group, get him to turn on Aspect of the Pack when Blistering Cold is cast. Remember to switch it off immediately when the Frost nova effect is cast.

Pro tip you never knew - Unchained Magic can be removed with Immunity effects like bubble and Iceblock.


Lich King
Ok i'm going to make this abit more comprehensive because if you can even reach this boss, you're not THAT much of a noob. You're probably just doing something wrong somewhere, so i'm here to correct it.

Phase 1
Best way i find to do this is to have the OT tank ALL the adds, and the MT just tank LK, and with the raid, they form a triangle.
Reason being you want to have as many adds for the Plague to jump to, so that it won't jump to your OT and waste a stack.It'll also make the transition less messy with all the adds in one place and your MT free to handle Raging spirits

Noob Mistake #1 - Infest-related deaths.
If you have a Disc priest, it's not possible to have any problems with this, and you should be 2 healing the encounter, but if you can't then just 3 heal.
10man- Otherwise, with a typical group of 3 healers, one healer should be on the tanks and 2 on raid. So just assign your 2 raid healers one group each to top up for Infest, once their group has no Infest left, he can help with the other group. Make sure they have Infest added to their Grid.
The tank healer can help with Infest too if there's no tank damage.
Tip: put your melee/tanks in one group if you have a shaman, so he can be assigned to Chain Heal that group for infest easily.
25man - same thing, just assign a healer a group. 
This just means your assigned group is what your first few GCDs are used for. Don't forget about the other group(s) after your group is cleared.

Noob Mistake #2 - Deaths to Shambling Horrors when running in to drop Plague
Do not be overzealous and run into the OT. You should only be running to the adds, maybe even just 2-5 yards from them, and the cleansed Plague will jump to the adds.
If you run too far in and end up in front of the Horror when it's casting Shockwave, you will probably get 1 shot.

Transition Phase
Remember to start moving LK to the edge when approaching 70%, and the raid should get ready to hop off.

Noob Mistake #1 - Deaths to Raging Spirits
From what i heard, Spirits spawn in front of where you're facing. Thus it's best to face the tank at all times to allow him easier taunting of the Raging Spirit.
And DON'T PULL AGGRO. I know you're eager to burn it down, but if any time you see that your threat is going past the tank, just hold back a little. 
Don't burst on a newly spawned Spirit, let the tank grab it for a sec first -_-

Noob Mistake #2 - Frozen Orbs wipe the raid
If one touches its target, it's most likely a wipe since it knocks back everyone in the vicinity. Make sure when you're running back in after transition that you let the RDPS assigned to clear the orbs finish them up before going all the way in.


Phase 2
While in 25man it's a good practice to stack offcentre to control the direction of the 3 Valkyrs, it is UNNECESSARY for 10man. Just stack dead centre in 10man, it's fine.

Noob Mistake #1 - Dropping defile in the middle / wrong place
Defile should always always always be dropped off on the outer perimeter of the platform. When Defile is about to cast, try to move outwards and spread out. The worst place to be in is the middle.
- another common mistake is dropping Defile where the valkyr is flying. If a valkyr is flying middle->right, you should be avoiding that path as much as possible if you have Defile so that your DPSers can still DPS the Valkyr


Noob mistake #2 - Defile/Valkyr timers very close and hence screwing up a call
Hate it when the timers are like 2-3 seconds apart? 
The best way to handle this is when this situation occurs, instead of stacking up for Valkyr (whichever one comes first), just make a small circle in the centre (approx radius 5 yards). 
This allows you to spread out if it's Defile and if it's Valkyr it's not that bad, you're not that far to the side.

Noob mistake #3- DPSing LK when Raging Spirits are still up
Make sure you finish up all the Raging Spirits before even touching LK! Don't just stack in the middle after transition and forget you still have adds leftover from transition.

Remember to move LK over to the edge when you're at 41-42%ish. It's ok if a Valkyr is going to spawn at t his point, just push the boss over and the valkyr will drop your teammate on the extended platform.
Tip: This may be a good time to use AM (with Frost Resist Aura on) or DSaC to minimize the damage from the 1-2 ticks of Remorseless WInter you're bound to take.

Transition Phase #2
Bloodlust once Raging Spirits spawn. Same things as before.


Phase 3
The best way to do it is to tank LK at one of the sides of the platform. When he summons Vile spirits, kite him across to the opposite side of the platform, and the RDPS can try to kill as many Spirits as possible
This allows maximum distance for the Spirits to have to travel to explode on you.

Noob Mistake #1 - Getting multiple Vile Spirit Explosions at a time
The key here is to STAGGER explosions.
Once the Spirits stop swaying around and start moving towards the raid, the raid should start moving, CONSTANTLY, especially so if a spirit is chasing them.
If you keep running, there's no way 2 spirits are going to blow at the same time on you unless you're really stupid and run into another one
Tip: It may be good to have your Offtank (the one not taking LK atm) stand in the middle and taunt a couple of spirits over to him, since he can soak a few.
- another way is to have a paladin bubble and just run around the middle soaking explosions from the spirits before they reach the raid.

Noob Mistake #2 - Dropping Defile in the middle
As before, this will make it hard for raid movement across the platform, so always try to drop it off at the side.

Noob Mistake #3 - DPSing LK when Raging Spirits are still up
As before, kill Raging Spirits before touching Lich King. 

Noob Mistake #4 - Releasing spirit after Fury of the Frostmourne
You really did this?

~~~~

Ok if you have actually reached this point and have finished all the bosses of normal mode.. grats! You've graduated from just a noob to a noobwithachievements. Now you can go flash the fancy 'heroic' word in your trade spams and parade your leet Kingslayer title, while i dance around you in my Bloodbathed Frostbood Vanquisher.