The Temple of Atal'Hakkar

The Temple of Atal'Hakkar, frequently called Sunken Temple is a level 50-55 instance in the Swamp of Sorrows. The item drops here are very good and can be worth doing even at level 60. The time for a run varies because some parts can be skipped. Expect a minimum of 2-2.5 hours for an Eranikus kill. A full clear could be up to 4 hours. The zone respawn is pretty long, and the dragon types never respawn so you can frequently return to right where you died in a wipeout.

Quests

Into The Temple of Atal'Hakkar - Alliance
Reward: Guardian Talisman
This quest line starts from a drunken dwarf in the hinterlands. You just need to pickup some ground spawn tablets, they are very common both inside and outside the instance.

Pool of Tears - Horde
This quest starts a quest line that will send you back to the temple. For this quest you just need to pick up some ground spawn tablets.

The Temple of Atal'Hakkar - Horde
Rewards: Guardian Talisman
This is the followup quest to Pool of Tears. You just need to kill some trolls.

Into the Depths
Reward: Hakkar'i Breastplate and Hakkar'i Shroud and Mark of Hakkar
This quest starts from the goblin in the center of tanaris. It sends you to the temple basement to click on the altar of hakkar and receive some items.

Secret of the Circle
This quest also starts from the goblin in the center of tanaris and gives you a hint to spawn the boss in the basement.

Zapper Fuel - Horde
This quest is part of a quest line that starts from Larion in the Refuge of Un'goro Crater. You need to get some haze off the basement monsters of the temple.

Haze of Evil - Alliance
This quest is part of a quest line that starts from Muigin in the Refuge of Un'goro Crater. You need to get some haze off the basement monsters of the temple.

Jammal'an the Prophet
Rewards: Helm of Exile or Rainstrider Leggings This quest can be tricky to get in a hostile troll ruins but there is one friendly creep who will give you a quest to kill the prophet in them temple.

- The God Hakkar
Rewards: Gemburst Circlet or Lifeforce Dirk or Avenger Helm
This is part of a quest line from a troll at the docks in tanaris. It has a few difficult steps to complete before the final step of killing Hakkar.

The Essence of Erankius
Rewards: Chained Essence of Eranikus This comes from a drop off the last boss Eranikus. You can then turn this item into the night elf in the cave in SE Swamp of Sorrows to get a later quest.