Mana Bomb
From WoWWiki
Mana bombs are powerful explosive devices developed by Kael'thas Sunstrider's blood elves for use against enemy spellcasters. The exact workings are unclear, but it appears to utilize some kind of massive mana burn that kills its intended targets almost instantly.
Kael'thas utilized these vile weapons to remove what he perceives as "obstacles". He has used this weapon twice: A Broken draenei from Tuurem suicide-bombing the Cenarion Thicket in Terokkar Forest, and bombing Kirin'Var Village in Netherstorm. A third is prepared in the courtyard of Firewing Point, the closest of Kael'thas' outposts to Shattrath City, for use against either the Allerian Stronghold or Stonebreaker Hold (the Alliance and Horde bases, respectively, near the edge of the Bone Wastes) or possibly Shattrath itself. After a series of quests investigating what happened to Cenarion Thicket and discovering the blood elves' complicity, adventurers from both sides are tasked to attack Firewing Hold and set off the bomb before it can be used; the final code to set off the bomb is held by a Blood Knight named Sharth Voldoun, who resides at the top of the tower high above the courtyard.
