Eranikus, Tyrant of the Dream

While the Sunken Temple questline has not been continued, Eranikus features prominently in The Scepter of the Shifting Sands quest chain, with the player required to obtain the green scepter shard from the green dragon. Upon visiting a spectral form of Malfurion Stormrage near Eranikus' shade in the Sunken Temple, the player is instructed to gather shards of the nightmare from each portal to the emerald dream.

Malfurion Stormrage gives this text to the player, which might give some insight into who is effecting Eranikus:

Malfurion Stormrage bows.

''Malfurion Stormrage says: Be steadfast, champion. I know why it is that you are here and I know what it is that you seek. Eranikus will not give up the shard freely. He has been twisted... twisted by the same force that you seek to destroy. Malfurion Stormrage says: Are you really surprised? Is it hard to believe that the power of an Old God could reach even inside the Dream? It is true - Eranikus, Tyrant of the Dream, wages a battle against us all. The Nightmare follows in his wake of destruction.''

''Malfurion Stormrage says: Understand this, Eranikus wants nothing more than to be brought to Azeroth from the Dream. Once he is out, he will stop at nothing to destroy my physical manifestation. This, however, is the only way in which you could recover the scepter shard.''

Malfurion Stormrage says: You will bring him back into this world, champion.

The player is then sent to Keeper Remulos in the Moonglade, who opens a portal into the heart of the Dream over Lake Elune'ara, from which Eranikus emerges. The player and his or her raid party are then required to defend Keeper Remulos from dozens of Nightmare Phantasms. As the phantasms were defeated, Eranikus lands himself. Eventually, Tyrande Whisperwind arrives with a half-dozen Priestesses of the Moon. Tyrande channels the powers of Elune in a prayer to redeem the cursed dragon.

Ceasing to fight, Eranikus changes into the form of a night elf, apologizing for all the harm he had wrought, and leaving to attempt to begin to make amends for his actions. He returns to Malfurion, Cenarius and Ysera to continue the battle raging within the Emerald Dream. A global world message will display for all players on the server after his defeat: Eranikus, Tyrant of the Dream, is wholly consumed by the Light of Elune Tranquility sets over the Moonglade.

Strategy
Have the raid split into 3 groups of healers and placed in the long house where Remulos stands. Warriors, melee are to stand near Remulos. During this battle, the objective is keep Remulos alive. He himself can tank a good number of the Nightmare Phantasms. Warriors are to taunt and drag the shades away from the healer group and back to Remulos so they do not get shadowbolted. Druids should heal Remulos, other classes on the raid. Keep deaths to a minimum as the shades will grow in size and power for each death that happens.

When Tyrande appears the entire raid can move out and full DPS on Eranikus, all heals should now go to Remulos. If anyone is taking damage, Tyrande will periodically cast "Mass Healing" that can heal the entire raid for about 2000 a tick. Melee should avoid getting breathed on.

As of Wrath of the Lich King, this is now soloable with only moderate difficulty. (As the guard NPCs are higher level.)