Did this quest on my shammy and then next morning went through to take two guidie friends on it. Had read a lot about how hard or even impossible this is and also heard lots of stories since about failed attempts on this server (Thunderhorn). Had two successful runs with no wipes and so thought I would share how we did it.

Class mix:
Group 1: Shaman x 3 (one rest/enh, two enh/ele), mage and warrior. All well decked out in blues and odd purple.
Group 2: Shamans x 3, priest and warrior (warrior well decked out in purple, rest blues)

Issues with this fight are the duration requiring mana conservation, and a hard point where burst damage is needed, where most people keep wiping (see notes below on the 3rd wave, green mobs). All mobs are lvl 60-61 undead and immune to war stomps and stunning (exception being grenades which I am pretty sure did stun them). At the end of each wave an "Aspect Of" spirit appears, which is bigger than the regular mob. Killing it triggers the onset of the next wave. We fought from the SW corner on the pile of bones both times. Apparently this fight was made harder a few patches ago. There are very few points in the fight where you get to drink and eat (and then only for a few seconds), so bring first aid and lots of mana pots! The fight lasts 20-30mins.

The Waves:

1) About 10-15 non elites (?red)- moderate hps, easily taken out by a well supported mage. 3 shamans with magma totems did it easily too. Easy.

2) About 15 elites (blue) - one group spawned as a mob of 4 or so, the rest spawned alone or in pairs and headed our way. They don't do a lot of damage but have a fair amount of hps. Just keep up the damage on them, use first aid when you aren't fighting and keep your mana stores not depleted to heal the tank. They do place a curse that increases physical damage by 90 for 10mins.

3) About 12 elites (green) - this is the most difficult wave by far, and the one that people keep wiping on. They all spawn simultaneously, and although I have heard that people get aggroed by all at once, even right in the corner we got about 7 or 8 the first time run straight for us, and about 4 immediately, followed by another 3 10 secs later, on our second run. The spawn points were different each time so I don't know if you can pick the ideal corner. There may be luck involved. In any case we had to deal with about 7-8 elites that hit us all at once. A hard ask as they do hit hard and have a load of hps. Our strategy was to have the warrior do an AE taunt, shield wall and take em all while the offtank (shaman) hit one, with all the others assisting the offtank. Take one at a time and unload everything, and once you have them down to 3 or so you are back to standard aggro management. If you look like you are wiping make sure your SS priest or shaman is right back in the corner. This didn't happen to us luckily!. At the end of this wave you will no doubt have no mana so make sure you shackle the "Aspect" and wait til health and mana are back to full. Our first group didn't have a priest so just kept popping mana pots and first aid, and moving to the next wave.....

4) About 10-15 elites (purple) - these guys keep wandering over in ones and twos, and if you get behind in killing them they pile up so you have to get a balance of killing them quickly enough but allowing time to regenerate health and mana by any means available. The fire shadow bolts from range so need to be silenced or earth shocked to come and melee like any caster. Their dps seemed higher but they had less HPs than the third wave and were relatively straightforward

5) The Darkreaver - looks like the Baron in Strath. Has a lot of HPs and possesses group members (just purge it), but is actually a straightforward fight. Our tank noticed you can disarm him although he is immunne to stunning.

Ok hope that helps. Our second run was very smooth with a priest, actually I would call it easy, as we could shackle the "Aspect of" spirits and be at full health and mana for the next wave. Have all your damage talents online and ready for that third wave and you should be ok. Difficult but with a good group and lots of healing and tankage it is possible to do it without wiping. Now to try it as an all shaman group of 5!

overview: The quest involves four waves of nine elite ghosts apiece, plus an elite boss at the end. You can't just charge in all willy-nilly and expect to complete the quest. Unless, of course, you're uber-geared to the max in which case why would you need the reward helm in the first place? :)&nbsp Here's the method my friends and I use and it's never failed.

Ideal group: Well, I'm a priest, so I've never done this quest without a priest. Priests play a roll in making this easier, but I'm thinking it could be done with a resto druid too, so long as they know how to make the most of thier mana pool. Other than that, you could pretty much do this with any class. NOTE:&nbsp The more shammies the merrier, totems make the fourth wave of ghosts easier to deal with, as you'll see further down this post.
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Before you start the event: Have your entire group go the the corner that's to your right as you enter Rattlegore's room. I believe it's the south-east corner. You'll stay in that corner for the first two fights. IMPORTANT! STAY in that corner,NO ONE leaves. Again.. you'll see why later. Have the shammie set the summoning item in the center of the room.

first wave: The first wave of ghosts show up all at once. DON'T PANIC! They don't hit very hard, just pick them off one at a time. At the end of the first wave comes a "boss" ghost, called the aspect of somethingorother. If you have a priest, have them shackle this boss. The next wave of ghosts won't show up until the aspect ghost is dead. Keep the aspect ghost shackled 'til everyone is bandaged/mana'd up. There's no time limit, you can keep him shackled for as long as you like.
&nbsp &nbsp Once everyone is ready, kill off the aspect ghost and now comes the

second wave: The second wave is easy too. Nine ghosts, they don't show up all at once. Again, stay in the south-east corner and pull these ghosts to you as they appear. After the ghosts are all killed, another ghost "boss" shows up, again called the aspect of somethingorother. Now for this aspect, you don't need to shackle him. In fact, don't shackle him. Kill him right off, but when you do, make sure you are all in the south-east corner. This aspect lays a nasty +90 damage taken curse down on everyone, and if you don't have a mage or a druid, you'll have to wait it out. If you are all in the south-east corner, you won't aggro the

third wave: This is the wipe wave, and with good reason. They have a large aggro radius, and they hit pretty hard. They also have a stamina-weaking spell, which can make it hard for the healer to see just how close to death you really are :) For this wave you'll want to take these guys on three at a time. Here's how:
&nbsp The third wave consists of three groups of three ghosts each. Take a look across from you, in the south-west corner. The three ghosts there move around, occasionally one will meander out to the middle of the room, and meander back to the corner. Have your tank run along the south wall into that corner, but he'll have to time it so that he gets to that corner when the three ghosts are more or less bunched togther. If he's timed it well, he'll only pull the three. Then the rest of your group can follow the south wall and finish off the three ghosts. From that corner you can pull the other two groups to you at your leisure. tips: If your warrior pulls the middle group too and winds up with six ghosts, let him die. You can rez your tank and try again. He might not like that but hey.. that's what tanks are for! Another trick is to have the warrior pop a shield block when he runs into the corner. This buys the healer a little more time to move into the corner and start healing. Don't bother to shackle these guys, it takes too much time and mana, and the healer will pretty much be spam healing at this point. These guys hit pretty hard.
&nbsp Another aspect boss shows up after this wave. At this point, shackle him if you need time to regenerate health and mana, the last wave doesn't come 'til the aspect ghost is killed. After the aspect ghost is dead the

fourth and last wave shows up. These guys are also difficult, but managable. They are casters, and they cast a multi-shot shadow bolt that can do a pretty solid amount of damage. Here's where a multi-shammie party comes in handy. Have your shammies spam grounding totems. They absord the shadow bolts and make life easier for your healer.
&nbsp For this last group you don't need to stay in any particular corner. Feel free to move around. The initial group is about three ghosts, kill them off as fast as you can. The rest of the ghosts will show up on a timer. tips: These ghosts are on a timer, which means it's in your best interest to kill them off as quickly as possible, don't stop to regen mana. After the initial burst of ghosts they start showing up one at a time, at which point, if you need to, you can take turns staying out of combat to regen mana. conserve mana during this fight because the darkreaver shows up after this wave, and you won't get a break. (side note) There's an aspect ghost after this wave too, just kill it off right away. The reaver shows up whether the aspect is dead or not.

Congrats! You've made it through all the notorius ghost waves! Now you get to contend with

The Darkreaver: This guy is a straightforward fight, no tricks, other than a mind control that's easily purged. He's the easiest part of the quest, really. Kill his butt&nbsp and go get your nifty new helm!

over-all tricks and tips: Use an MA for this event. Pick someone to be the main assist and everyone target what he's targeting. It's less chaotic, it makes life easier for your healer and tank, and it's a faster way to plow through multiple mobs.
&nbsp Don't AOE! It might be tempting, 'specially in the first fight, but don't do it. Chances are, your healer is going to be busy keeping the tank and himself alive. Don't add to his burden by trying to mow down 5-8 mobs at once.
&nbsp If the worst happens, and it looks like it's going to be a wipe, everyone run back to the south-east corner. You can safely rez and regroup there to try again. Don't release! Once the event is started, you can't get back into the room again until the instance is reset.

I hope this helps clarify how to do this quest. I'm sure it's not the only way to do it, but it's seemed to work for me and my friends. Good luck!

Before the event is triggered, the group will want to go to the corner you'll face by entering the basement and turning right 90 degrees.

There are four waves. After each wave, you fight a named mob called "Aspect of [something]".

Wave 1: As soon as the Divination Scryer is placed, 9 or so very slow moving mobs spawn. It is recommended that the shaman kite the slow movers around the room, making them even slower with earthbind totems. The shaman should be able to avoid taking damage the entire time. One of the other party memebers should start pulling each mob off of the shaman one by one and training it to the rest of the group, who should kill it.

Kill all 9, a named comes. Make sure that everyone is in the corner mentioned earlier when the named dies.

Wave 2: Mobs will spawn one at a time. Once you kill one, another will spawn.

Kill all 9-ish, another named appears. Again, make sure you're in the corner when he dies.

Wave 3: 3 linked groups of three spawn. It is recommended that you take the group out by the enterence first. If you have a warrior, have him hug the wall and charge one of the three in that group when they are furthest away grom the middle group. If he accidently pulls the middle group, let him die, res, and try again. If he succeeds, the rest of the part should hug the wall to the other side and take out the group of three. Afterwards, take out the middle group, then the far group.

Kill all three groups, a third named spawns. Again, make sure you're in the corner when he dies.

Wave 4: One mob spawns, then subsequent ones spawn on a timer. It is important to DPS each one as fast as possible, as these hit hard. You can make life easier by dropping a grounding totem, as that will absorb their hard-hitting range spell. If you have two shamans in the party, it makes it MUCH easier.

Kill all 9-ish, another named appears. Kill him, Death Knight Darkreaver spawns. Kill him for the win!

I agree with the above, that this is not difficult.

My addition to all the information here is this:

The end of each wave is marked by the appearance of a named ghost called "Aspect of <something>" where something is for example "Banality".

My opinions on the quest are as follows.

When I originally set out to do this quest, I was expecting that it would be as hard or harder than the Warlock epic mount fight in Dire Maul. In fact everyone was looking forward to a very challenging and interesting encounter.

What we got was a big disappointment. It was a long and boring slog through a mindless and uninteresting series of mobs. You have loads of time between waves to drink and heal up. Halfway through we were all saying "omg this is it?".

If you have a warrior, a priest, shaman, warlock and mage you will have no problem. Heck, any type of moderately competent group should be able to finish this. Sit in the North East corner and just take things as they come.

It's not as easy as you say. Theres virtually no time for your party to rest between the fights unless you shackle the last mob and then just wait for your spirit to rejuvinate your health and mana. The only times you can rest are between the 2nd wave and the green ghosts (if your in the NW corner). The only real problem my group had was that the Curropted Aspect (green mini-boss)wouldn't stay shackled so we couldn't restore our health and mana. The purples tore us apart since we went into the fight with half health and half mana. It may have also been that our dumbass warrior wouldn't take the aggro off the casters, but you never know.

I'll try your idea about keeping my out of battle so I can rez the rest of the party when they die. Wouldn't the mobs just aggro me after they've finished with my party though?

This quest was fairly easy for my group to complete. Mind you, this was coordinated over a vent, all guildies. The group:
60 warrior
60 priest
60 hunter
60 resto shammy
60 elem / enh shammy

You have to place the scryer in the upper righthand corner of the Rattlegore room, while the rest of the party stands in the bottom lefthand corner. The ghosts spawn in 4 waves. Generally, you will want to stay in the corner and pull the ghosts to it so as to avoid adds.

Wave 1: Easy. Just a bunch of nonelites.

Wave 2: Just pull em one by one and drink between fights. No problems.

Wave 3: The Green Ghosts. If you have a hunter, have him pull the ghosts. If he's good, he can get 3 per pull. If he gets more than three, have him feign death. Retry til you get a good pull. When you do, lay a disease cleansing totem, because these ghosts have a disease that decreases sta substantially. Then, just proceed as normal with undead mobs (shackle, etc.). Now, when the aspect spawns, be mindful that in Wave 4, you will need to begin dpsing immediately. Therefore, CONSERVE mana. Shackle the aspect if needed, then let spirit + mana spring/tide totems get you up to full before finishing the aspect off.

Wave 4: Easy if you know what to do. Just dps the ghosts as soon as they spawn. Drink as needed, but just realize that the ghosts are on a timer and you will need to get them down quickly or you will have many ghosts to deal with and you will wipe.

Boss: Not much to say here... we had no problems, just took some time. Switch off healing if needed (shammy takes over when priest gets to 50% mana). No special tactics really.