Kill Arazzius the Cruel, then return to Nazgrel in Thrallmar.
Magister Bloodhawk finally deciphered the Legion missive you found earlier. It turned out to be attack plans sent by one of Highlord Kazzak's lieutenants - Arazzius the Cruel. Apparently, Arazzius commands the Legion ground forces in Hellfire. The time has come to terminate his command, <name>. Terminate with extreme prejudice.
Head west to the Pools of Aggonar and put an end to this so-called 'Legion lord'. Today, the Horde reclaims Hellfire Peninsula. Let the Legion be damned.
You can choose one of these awards:
Also, you get: 8 70
Destiny calls, <name>. Arazzius the Cruel has eluded justice long enough. Let his death be a message to all those who would oppose the Horde. You are next.
For generations to come, they will sing songs of this day, <name> - songs of your valor. I wish Thrall had been here to celebrate this victory with us. The Legion is undone - and Hellfire now belongs to the Horde once again! There may yet be hope for this ravaged world - and our peoples' place within it.
Upon completion of this quest you will gain: