Mission: End All, Be All

Do you know what would have happened if you had not intercepted this missive, $N?$B$B<Nazgrel nods.>$B$BThe entirety of the Legion army in Hellfire would have been knocking on our door. There is no way that we could have survived such an assault.$B$BThere is only one way to make sure that these orders never reach the Legion Front. You must travel to the Pools of Aggonar, west of here, and slay this Arazzius creature.$B$BDo this and I will see to it that the Warchief grants you a commendation.