Are you familiar with Shattrath City, $c?  Above it to the northwest is a place called the Barrier Hills, which you can only get to upon a flying mount.$B$BOne of Gruul's sons, Slaag, exiled himself and took control of the Gordunni ogres that reside there.  Even at such a distance, we cannot afford to leave him in peace, lest he return when the rest of his brothers have been slain.$B$B$N, you must travel there, and bring back his standard as proof that he has been dealt with.