Update: added a new dungeon to the OP, the Nightmare Vault, and a new type of endgame content below.
NEW CONTENT TYPE - LABYRINTH
A labyrinth is a sprawling 5-man instance created for pre-made groups to explore and complete at endgame. With a massive location, a three-day reset cycle, and special quests and bosses that change with each reset, it will provide exciting new challenges and changing content for players to explore. Additional bosses and missions will be added with each patch cycle, adding extra challenges for advanced players.
The Temple of Atal-Hakar
The Sunken Temple has long been a weak spot between the physical world and the Dream. Nightmare corrupted dragons once filled the bowels of the temple as jungle trolls tried to raise slain demigods above.
Now the trolls who invaded the Dream have withdrawn here with secrets they’ve stolen from the Naga. They’ve barricade themselves within the temple, as the naga invade from the sea and Nightmare dragons and druids cross over into the depths of the dungeon. Carve your way through these forces and discover the powers the trolls wield.
The Labryinth will include the entirety of the original Sunken Temple, its exterior approach, and even the surrounding lake and shoreline. Alliance players will start in the Marshtide Watch to the north, while Horde players begin as a Stonard expedition on the west coast. Battle waves of naga (and perhaps the other faction) to get into the temple. Fight to the bottom of the temple and defeat the Nightmare’s forces to get the troll priests to lower their barriers. You are powerful and will be a worthy sacrifice to their blood god!
Defeat the trolls to learn that they are bringing Hakkar back in a bid to save their homeland.
In patch 6.2 a band of infinite raiders will arrive, providing (optional) harder opponents that will give improved rewards. In 6.4 you can return to battle the spirit of Hex Lord Malacrass, extinguishing him for good.