Speak to Borsh in Kor-Gursha.
Borsh tells you, "There are monsters lurking in the fetid recesses of the Southern Catacombs, huge and bloated with dark purpose. Take your weapon and hunt down 10 of the Guruk Monstrosities and I will reward you. Be careful human, those are dangerous caverns."
Borsh tells you, "Thank you, I can sleep soundly for a time. Accept your reward my friend."
You've earned 32,483,000 experience.
Borsh tells you, "You will be forever remembered as a "Monster Killer".
Borsh tells you, "I'm sure those monstrosities will crawl back from their holes soon enough. Come back in a couple of weeks and I'll reward you for another hunting trip."