Doan Karhan is a level 40 quest giver located in a small camp east of Camp Taurajo in the Horde-aligned territory of the Barrens. He is friendly to both Alliance and Horde. He owns the "Orb of Zargain", an orb similar to Orb of Soran'ruk.
He starts the quest  (Dungeon).
See List of the Barrens NPCs