I wrote draft posts about Rotface/Festergut while I was in AK, but I can't seem to find Festergut! If I can find it, I'll post it, otherwise I'll have to re-write it.
In any case:
Boss #2 in Plague wing is here for all you dps DK min/maxers!
I've now had the opportunity to not just kill Rotface and Festergut a few times, we did manage to kill the Professor as well, so his 'guide' will be out shortly, along with Blood Princes who've also bitten the dust a few times for my guild (several kills now since I wrote this - along with Valithria but not BQL or Sind/Arthas yet).
Rotface has less dps/gear requirements than Festergut, but has considerably more coordination required, and has been killed by fewer guilds on most servers.
Pull/Phase One: Summon your army on countdown for the pull. You'll start your normal rotation, including use of your ghoul/gargoyle/drw. You should get them back towards the end of the fight. Obviously, you'll stand behind Rotface. Some raids will clump into groups to minimize too many people getting caught by slime spray. My guild prefers to have everyone clump behind Rotface and run behind him when he sprays. It's easy to avoid and really nobody should get hit by it. What I do is stand at about a 45 degree angle behind him; when he sprays, I don't have to run straight across and do a 180, I just strafe behind him again, dpsing all the way.
When you get mutated infection, pop anti-magic shield, and strafe once again to the ooze kiter. You can Icy Touch and Death Coil - basically not lose all your dps while you're at range - while you wait to be cleansed.
I've noted that in many videos I watched everyone runs out/scatters when the ooze explosion notification pops up on DBM. Don't do that. Just stay on the boss until the MT kites him out of the center (as long as he does move out), dpsing all the way. If you happen to get hit once or twice, use an ability to keep your health up - death strike, icebound fort, etc. DON'T army of the dead with oozes up, as the ghouls will taunt them, potentially causing a wipe. Be wary of which quadrant the ooze flood is in; most people will want to avoid it altogether, but if you happen to have AMS up, you can pop it and dip into the ooze for free rp if you are away from the boss due to mutated infection anyway.
At the 30% mark, when oozes spawn so much faster, be ready to burn hard. Some guilds will heroism/bloodlust then, so pop your speed potion, and summon your pet again if the cd is up. Go to town! You have enough defensive cooldowns that you shouldn't die easily in this phase. Which is good, since dead dps do no dps at all. As before, any spec is theoretically viable for this fight, although Frost is in bad shape in general. It's probably best used only if your raid doesn't have an enhancement shaman for windfury. So, if you avoid the few aoe damaging things that can kill you, properly kite the small oozes, and maximize your time on target, you should do pretty good dps, somewhere in the vicinity of 7k in decent gear.
A few miscellaneous tidbits that might not be applicable to all (feel free to ignore). Once you are in 2pc T10, you'll be focused on maximizing your main Strikes (heart/scourge/etc) above Death Coil. You may find it hard to ignore a full runic power bar in favor of FUFU (frost/unholy rune) Strikes, but your dps will suffer if you let your runes sit idle. Some prefer to wait until they are in full T10 before switching, but I felt the upgrade from my two 232s to 251s was enough to justify the switch from 4pc bonus. Many people will have the 4pc T10 by now - I've missed a fair bit of raids with my guild transition, but will have it this week, along with the crafted legs and Shadow's Edge Stage II (I almost have my 1000 souls). For those fortunate enough to be at this point - NOW it's time to rock and roll, baby! T10 gear has some serious dps potential!