Black Stone

Source
This item drops from:
 * Anubisath Guardian in Ruins of Ahn'Qiraj
 * Anubisath Sentinel in Ahn'Qiraj
 * Obsidian Nullifier in Ahn'Qiraj
 * Obsidian Destroyer in Ruins of Ahn'Qiraj
 * Obsidian Eradicator in Ahn'Qiraj
 * Anubisath Defender in Ahn'Qiraj
 * Anubisath Warder in Ahn'Qiraj