Atiesh, Greatstaff of the Guardian
Atiesh is broken into 42 individual pieces and scattered to the wind as a result of Archimonde's assault on Dalaran during Warcraft III. All the pieces must be collected in order to reform the staff. Then the staff must be exorcised in order to expell the evil taint of Sargeras from the staff.
The miriad of bosses in the Naxxramus Necropolis all have a chance of dropping a Splinter of Atiesh. Once 40 of the splinters have been gathered by someone, they combine to form the Frame of Atiesh. Once the frame is formed, it begins a quest, which leads you to speak to Anachronos, but not before you have the chance to witness the death of the Archmage at LHC who first tipped you off to the whole thing in the first place.
(8-23-06) Sera, of <Vis Maior>, on Bonechewer Alliance, is the first known person to aquire all 40 splinters and form the frame.
Anachronos then sends you to collect the head and base of the staff. The head is held by none other than Kel'Thuzad himself, a powerful Lich, second of Arthas the Lich King, and Lord of Naxxramus. The base was held by Brann Bronzebeard when he entered the ruined Temple of Ahn'Qiraj, but now he has since left, and the base is now held by C'Thun, remanent of the Old God. Once the Head and Base are both aquired, you return to Anachronos. He then tells you that the demon possessing the staff must be purged before it is safe to use. Inside Stratholme lies the patch of concecrated earth. Once you exorcise the staff, a demon named Atiesh, Hand of Sargeras appears. Once defeated, you receive the legendary staff.
(9-9-06) Congratulations to Failure of the guild <Risen> on the world's first aquisition of the staff.
Splinter of Atiesh Binds when picked up Classes : Priest, Mage, Warlock, Druid Requires level 60 Use : Combines 40 Splinters of Atiesh to form the Frame of Atiesh.   "A splinter of Atiesh, Greatstaff of the Guardian"   Frame of Atiesh Binds when picked up This Item Begins a Quest Requires level 60 "The head and base are missing."
Atiesh, Staff of the Guardian (Mage) Binds when picked up Two-Hand Staff 130 - 244 damage +31 Stamina   +32 Intellect   +24 Spirit   Requires level 60   Equip : Improves your chance to hit with spells by 2% Equip : Increases damage and healing done by magical spells and effects by up to 150. Equip : Gives party members within 30 yards a chance to get a critical strike with spells by 2%. Use : Creates a portal. Teleporting group members that use it to Karazhan. Atiesh, Staff of the Guardian (Warlock) Binds when picked up Two-Hand Staff 130 - 244 damage +30 Stamina   +29 Intellect       Requires level 60   Equip : Improves your chance to crit with spells by 2%. Equip : Increases damage and healing done by magical spells and effects by up to 150. Equip : Gives party members within 30 yards increased damage done by magical spells and effects by up to 33. Use : Creates a portal. Teleporting group members that use it to Karazhan.
Atiesh, Staff of the Guardian (Druid) Binds when picked up Two-Hand Staff 130 - 244 damage +28 Stamina   +28 Intellect   +27 Spirit   Requires level 60   Equip : Restores 11 mana per 5 seconds. Equip : Increases healing done by spells and effects by up to 300. Equip : +420 Attack Power in Cat, Bear, and Dire Bear forms only. Equip : Restores 11 mana every 5 seconds to party members within 30 yards. Use : Creates a portal. Teleporting group members that use it to Karazhan. Atiesh, Staff of the Guardian (Priest) Binds when picked up Two-Hand Staff 130 - 244 damage +28 Stamina   +28 Intellect   +27 Spirit   Requires level 60   Use : Increases healing done by magical spells and effects by all party members within 30 yards by up to 62. Use : Increases your spell damage by up to 120 and your healing by up to 300. Use : Creates a portal. Teleporting group members that use it to Karazhan.