Zhar'doom, Greatstaff of the Devourer

Zhar'doom, Greatstaff of the Devourer is an epic staff for DPS casters.

Source
This item drops from Illidan Stormrage in the Black Temple.

Trivia
The name may be a reference to StarCraft, considering that in some levels and the Map Editor you were able to add a zergling hero called "Devouring One", and the Felhunters that this staff is modeled after bear a passing resemblance to zerglings.

The name "Zhar'doom" also appears to be a reference to Zha'dum, the homeworld of the Shadows in Babylon 5.