Black Rat
This NPC can be found in Razorfen Downs (28), Duskwood (22), Western Plaguelands (20), Icecrown Citadel (25), The Forge of Souls (9), Utgarde Keep (18), Pit of Saron (8), Halls of Stone (7), Ahn'kahet: The Old Kingdom (5), Coilfang: The Slave Pens (4), Violet Hold (3), Shadowfang Keep (12), Utgarde Pinnacle (7), The Sunwell (4), Drak'Tharon Keep (4) and Scholomance (1).