The Guardians of Hyjal are a new faction that will be appearing in World of Warcraft: Cataclysm. See the related link for more detail.
Nordrassil is located in the Mount Hyjal zone, or will be when the Cataclysm expansion hits.
Yes, Mount Hyjal will be accessible in Cataclysm when it hits the stores. It will be for high level characters to level in. There will also be an instance located there.
Mount Hyjal will be one of the new zones in the upcoming expansion Cataclysm. It will have a brand new dungeon, Firelands. This dungeon will be both 5 man and 10/25 man dungeons. Mount Hyjal was previously accessible to players, but later was closed off. I will be controlled by three factions. They are The Black Dragonflight, The Guardians of Hyjal, and The Twilight's Hammer Clan. Note: This information is considered sketchy at best as Blizzard may decide to change things before Cataclysm's release.
Iris Moondreamer is a non player character in World of Warcraft. She sells her gear at Nordrassil Inn in Mount Hyjal.
In World of Warcraft, the term 'Ancient' most often refers to beings of incredible power that are seen in alot of the game's lore. Some quests in Mount Hyjal are about reviving the ancient beings to save Hyjal. In Mount Hyjal, there are NPCs and areas dedicated to them where you will be told about the lore behind them. These ancients are known as Aviana, Goldrinn (or Lo'gosh in Orcish), Malorne and Aessina. The term ancients can also refer to large natural beings found in Kalimdor. They are often seen in Darnassus where they serve as guardians to the city and allies of the night elves. They are based on elements, and look very similar to trees, but occassionally are shown to have tusks, charms, and lanterns on them. They look very much like the druid's Tree of Life Form only far bigger.
The dead tree is near ratchet in a open field full of creatures on the left
Archimonde is one of the great Eredar demon lords, hailing from the world of Argus. His most notable feat was the destruction of Dalaran - capital of the Kirin Tor - and his subsequent defeat at the hands of Horde and Alliance heroes as he attempted to drain the power of the World Tree in Mount Hyjal.
depending on what realm and what the population is comes into play as far as off peak times. i personally play on a high popualtion realm hyjal and the off peak times i notice is 3am to 7 or 8 am server mostly so hope this helps
The Ogre Outhouse is mentioned in the quest "Seeds of Discord" in Mount Hyjal. The outhouse is located in the east-most part of the Twilight Enclave there. Its in-game location is 77.5, 48.0. It can be hard to spot, because despite of its name, it's smaller than you'd expect.
There is no such thing as World of Warcraft: The Frozen Throne. It is called Warcraft 3: The Frozen Throne. World of Warcraft is much different.
World of Warcraft is set in Azeroth...
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