The strategy used for managing the stacks is going to vary a lot from guild to guild, but here's a couple of tips.
Scary Fog tanks can be affected by each others debuff. Be careful not to run over each other, especially dangerous when switching during get away. Get away damage + double fog = GG.
I refresh stacks as the protectors are spawning, or right before. Then head over to skull quickly, while carefully avoiding debuffing tanks with scary fog.
I generally will disengage out to refresh stacks with 18 sec on debuff. If you miss the refresh that happens around 17 seconds and then she hides, or does get away and you only have 10 sec left on Fog then it will be hard to recover.
Deterrence deflects 100% of the get away damage, this is godlike if you are doing high stacks.
When we realised the healers (we 3 heal) could easily keep my up with 20 stacks we simplified our strategy and it helped a lot. Many guilds use a 3rd tank to take 20 stacks but a hunter is very good for it with Iron Hawk, Animal Bond Glyph and Deterrence. Being able to DPS while sticking to the boss for Get Away is nice also.
We use 2 Fog tanks, hunter and warlock. I aim for 20 stacks fast, warlock initially debuffs the boss and gets to 10 stacks slowly then drops his stacks and I solo the rest.
On the pull warlock + hunter stay out so we can build our stacks. Healers stagger in stacks to the boss to optimise DPS on the first burn. ie. Priest runs in on the pull with 1 stack, Druid runs in once he has 2 stacks, Paladin runs in with 3 stacks. Then the warlock takes over.
If the boss does Get Away we send in whoever has the highest stacks, but other than that the warlock debuffs the boss full time and portals in/out to refresh stacks.
When the warlock gets 10 stacks and drops his debuff I take over.
After 12 stacks or so I make sure to use a full deterrence for each Get Away! to help out the healers. Crouching Tiger, Hidden Chimera is necessary for this.
It all depends on who your other soaker is. I do the stacks in our group, but our other soaker is our frost DK who respecs blood for the fight and just roflstacks the Fog while I alternate in and out. He grips the skull add during protect, and with 20+ stacks on it, the thing melts.
The most important thing is to A) refresh your stacks right before a special ability, and B) know when a hide may be coming, because that's the easiest place to drop a stack. The abilities always come in sets of 2, if the first ability is Get Away, the next will be Hide. Then, it resets. So, you can get Get Away, Hide (reset), Hide, Get Away (reset), Hide, Get Away, (reset) Get Away, Hide, etc.
EDIT - sounds like we did it differently than some people - but we were switching in and out every stack.
on 25 man, myself and the other hunters are soakers. the tanks and hunters both have set places to stand. the hunter with the refreshed buff would come in from the right, the hunter leaving exited left (counter clockwise motion) so we didnt run over the tank. every time we got a new stack we would run in and the other would run out.
you have to have the rest of the group be QUICK on hides. you're screwed if you lose the buff.
use lock portals to get in place for get away - we had everyone in a specific spot for this so they didnt get run over with the fog. the fog soakers had the right side of the room - everyone else needs to stay away - it's difficult to stay in position. make sure everyone stays clear.
also - not specific to soaking but glaive toss during the adds is bad
make sure your healers realize you need to be healed AS A TANK - that means they need to plan CDs around the hunters esp on the higher stacks. The most danger is during get away, the healers need to be sure to be close enough to the boss that they stay in range of the soakers.
make a weak aura that tells you when the debuff is on the boss and one that tells you how much time you have left on your stacks. ideally you're switching everytime each of you gets a new stack but even if the other guy doesnt come in you will need to leave about 17-18 seconds left on yours to make sure it doesn't fall off.
during hide get far away from the spot where he's coming up. if you're inside the circle when he pops up your stack will not refresh and you're screwed. also on hide, make sure when you're running in to buff him to never stand in front of him.
once you get the hang of switching every stack, it's really not that bad. it will come down to your healers being able to keep you alive.
---------- Post added 2013-02-26 at 05:23 PM ----------
EDIT 2 - just saw this
Originally Posted by stances
I was solo doing the stacks. i was going out at like 17 seconds to go to refresh, is there a way I could do it sooner?
pretty sure there is a DBM timer that says when the next stack goes out so you could watch that to judge it better
Stacks go out every 10s or so outside the ring, so in theory, if you go in right after you get a stack, you can probably push 12s left before you disengage and be fine. I leave with 15s because it's not really an issue.
I'm raid leader and my job is to maintain stacks on the boss between the specials, dropping them at 10 or so. I basically move out of the center when I have ~15s left on fog, or a special is about to happen. I stay in if I'm above 10 stacks and a special is coming. We 3 heal it and kill the boss in under 6 minutes.