Scholomance

1) Enter the instance. Kill the mobs at the start. I you just charge forward, the other mobs jump down and aggro everything back up. Bug maybe? Quick way to die, even at 80.
2) Head down the stairs to the left. Unlock Iron Gate and enter the Chamber of Summoning.
(Kirtonos is in the large room to the North if you brought some Blood of Innocents)
3) Run through the chamber to the door on the West and keep going. You'll come to another room with Plagued Hatchlings in it.
4) Run through this room and down the stairs. Rattlegore is on a hill. Kill him. Get the Viewing Room Key.
5) Run back upstairs. Continue past the whelp room to the next large room. On the right is another door. Open that. On the right-hand side is another door that requires the Viewing Room Key. Open door and enter. The skeletons may be immune to spell damage. I died to them. Not sure though.
6) Ignore this room. Run through and go downstairs.
7) Kill Ras. He's part 1 of the achievement.
8) Head back to the viewing room. There's a door on the east side. Open that and go through.
9) Take the stairs down. There are 6 bosses to kill in here before the main boss. 3 up, 3 down.

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• Lorekeeper Polkelt - Nothing fancy. AoE his mobs if you can then attack him. Some mobs seem to reanimate.
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• Doctor Theolen Krastinov - Hits very hard.
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• Instructor Malicia - Heals. Clear this room.
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• Lady Illucia Barov - Died before she got to me, so not sure if she does anything.
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• Alexei Barov - Has 2 buddies helping him. Stuns. Clear this room.
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• The Ravenian - 36k health or so. Solid tank.
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10) Head out to main room. Gandling will appear. He has 50k health. The Coven and Barov Family Vault must be cleared before he shows up.

Quick tips if you are doing this at 70+ for the achievements.

Need the Skeleton Key to open the door to the instance. You can 'die' and rezz behind or go to the Bulwarks (Horde) and do the quest chain if you don't have the key (which is part of another achievement for obtaining dungeon keys).

Need to kill Rattlegore and loot his key to gain access to the room with Ras Frostwhisper.

Need to kill the six mini bosses (3 upstairs / 3 downstairs) in the Headmasters Study area and all mobs in The Coven before Darkmaster Gandling will appear.

The key quest chain starts with the surprisingly named quest Scholomance for the Horde and the aptly named Scholomance for the Alliance. Both quest chains involve traveling to Gadgetzan and Un'Goro crater and a payment of 15g. Also make sure to bring Thorium Barx2 before setting of to Un'Goro! Finally you'll have to defeat Araj the Summoner to get your key, which can eas