Set the Yaungol Banner ablaze to summon Ur-Bataar, and then defeat him in combat.
The yaungol have always been a difficult, proud people, but never this violent or aggressive. I do not know what has prompted this change in their behavior, but we don't have time to find out, now. We fear for our lives and livelihoods as long as Ur-Bataar, leader of the Bataari yaungol, lives. Go, set the banner in his camp ablaze to challenge him, and then defeat him in battle. Only then will we be secure.