Well of Eternity is a heroic-only dungeon in the Caverns of Time, released in Patch 4.3.0 as part of the progression on to the fight against Deathwing. The second instance is situated in a pre-Sundering Kalimdor, over ten thousand years in the past, during the Burning Legion's first invasion of Azeroth.[1] Players must go there to get the Dragon Soul, which will then be given to Thrall to be delivered to the Aspects at Wyrmrest Temple. Players will escort him as he carries the Dragon Soul to Wyrmrest in the third dungeon, Hour of Twilight.[2]
The instance follows the novel version of the war, minus the inclusion of Krasus, Rhonin, and Broxigar; although the three of them were not involved in the events depicted regardless, as they rode on dragonback during the battle in the novel. All players appear as night elves for the duration of the instance, similar to the Human Illusion in Old Hillsbrad Foothills and Old Stratholme.
The Dragon Aspects that occupy Wyrmrest Temple have a problem: They know that if they cannot destroy their fallen brother Deathwing, he'll consume the world. There's only one artifact with the power to weaken the Black Scourge, but it has long since been destroyed: the Dragon Soul (a.k.a Demon Soul). To retrieve the golden disc the Aspects must charge the heroes of Azeroth with its retrieval from the depths of time. Deathwing first unleashed the power of the Dragon Soul to stop Sargeras and the Burning Legion from entering Azeroth through the Well of Eternity. That means sending players to the Caverns of Time and Nozdormu. Upon arriving, the Aspect of Time will tell them that his ability to send them back to the battle at the Well of Eternity is being interfered with by an entity in the future. First then, players must go forward into the End Time and kill Murozond. Within they'll witness a charred vision of the world should the plan to defeat Deathwing fail. With Murozond's defeat, players will be able to venture into the past and partake in the near-apocalyptic clash at the Well of Eternity. There, players will fight alongside such prominent characters of Warcraft lore as Illidan Stormrage, Malfurion Stormrage and Tyrande Whisperwind. They'll see the demon Mannoroth and the delusional highborne queen, Azshara.
Dungeon Journal[]
Ten-thousand years in the past, the night elven capital city of Zin-Azshari was a magnificent sparkling metropolis. Situated on the shores of the Well of Eternity, it was here that the aristocratic Highborne first opened a portal into the Twisting Nether and invited the Burning Legion to invade Azeroth. Under the command of the night elven queen, Azshara, they now pour their energies into the portal, preparing it for the terrifying and glorious entrance of the demon god Sargeras.
Description from site[]
With a gateway to the past now open, Nozdormu will transport players to Azshara's palace, where you'll witness one of the most catastrophic events in the War of the Ancients, dating back 10,000 years. While assisting the much younger Tyrande and Illidan in a battle against the Highborne and Burning Legion, players will need to steal the Dragon Soul hovering above the Well. With so many of Azshara's most empowered wizards locked in ritual and pouring their magical energies into the turbulent depths of the Well, retrieving the Dragon Soul will require victory over some lethal foes.
The task at hand requires nothing short of total success. In order for Thrall and the Dragon Aspects to rally heroes of the Horde and Alliance to defeat Deathwing, you must steal the Dragon Soul from the distant past. However, the tragic events which took place at the Well of Eternity must ultimately come to pass, leading to the Great Sundering, the creation of the Maelstrom, and the loss of countless lives.[3]
Mannoroth and Varo'then
Doomguards
[35D] 
Icy Veins Well of Eternity walkthrough
