Hellak Darkhorn was a tauren warrior in the service of the Alliance. He mistrusts the orcs because he thinks they are to quick to fight and willing to do it dirty, because of their demon-tainted history. He felt that the humans possessed a core of honor, and he serves the Alliance as a scout.
During a scouting mission he had a run-in with H'jalla Danfour, Hellak told the human warrior that he was in the service of the Alliance, Hellak noticed but too late that H'jalla was in the service of the Horde. H'jalla had envenomed her weapon and the poison stopped Hellak's heart.