Auchenai Key
This key opens up the heroic mode of the Auchenai instances; Auchenai Crypts, Sekketh Halls, Mana Tombs and Shadow Labrinth. This Key costs 10 gold off Nakadu, lower city quartermaster in Shattrath. Requires reputation of honoured with lower city.

Key Of Time
The Key of Time opens Heroic mode Durnholde and Black Morasses. This key costs 10 gold off Alurmi, Keepers Of Time Quartermaster in Tanaris. This key requires honoured reputation with the keepers of time. To gain reputation with KOT you have to run the two instances, completing Durnholde before you are allowed to enter Black Morrasas.

Shadow Labyrinth Key
This drops in Sekketh Hall's in a box after Talon King Ikiss, all party members are allowed to loot this key, you will then be able to open the doors to the shadow labyrinth.

Shattered Halls Key

This was the most fun key to get, remember all those times as a lvl 60 being trample by the Fel Rever well now its payback time.
1.(67,37) Shadowmoon Valley, Drops from Smith Gorlunk.
Near the entrance to the Black Temple, there are two side's the smith is on the left side just up the first ramp, there are lots of high mobs and elites here, east to do if you can fly. HE drops the mold which starts the quest chain
2.(56,66) Force Commander Danath Trollbane.
Trollbane is up stairs in the middle of the fort
3.(51,60) Grand Master Dumphry
Dumphy is wandering around the west tower outside of honour hold, he will ask you to bring him
4 fel iron bars
2 Arcane Dust
4 Mote of fire
Then he will instruct you to kill a Fel Rever.
4. Kill a Fel Rever
All those time he hunted you down now it time to get him back, kill the Fel Rever and
use the key mold on him. Return to Dumphry and you will have the key.

Skeleton Key
This is the attunment for Scholomance, starts in Chillwind camp in Western plague lands and has you running around plagues lands and to Gadgetzan
1.Western plague lands
Get quest “Skeletal Fragments” off Alchemist Arbington
Enter Andoral and kill skeleton until you get 15 fragments, ghouls and abominations do not drop the fragements, return to Arbington and hand in. Pick up quest “Mold Rhymes with “
2.Gadgetzan,Krinkle Goodsteel
Take 15 gold and 2 Thorium bars to Krinkle, he exchanges the 15 gold for a skeleton key mold.
3.Fire plume ridge
Take the mold and thorium bars to the top of fire plume ridge, using this here will give you an unfinished skeleton key.
4.Western plague lands, Alchemist Arbington
After picking up the quest Return to Andorhal and kill Araj The Summoner
5.Return to Arbington to collect you key

The Violet Hold Key

This is most probably the easiest key to obtain, Enter the violet Citadel and pick up the quest off Rhonin the leader of the Kirin Tor, you need to be level 75 to pick up this quest. He then directs you to Warden Alturas outside the Violet Hold, you will be presented with the key in order to complete the next quest.

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