Find Captain Tillin in the Arena at 49.34, -511.83, 31.75
You say, 'hail Captain Tillin'
Captain Tillin says 'Hail, Runengetum ! Spend your time wisely in the city of Qeynos. Do not let your mind wander to thoughts of bravado or crime. My guards can easily put to rest any outbreaks. Good day to you, citizen!
You say, 'I wish to join the fight'
Captain Tillin says 'You fancy yourself a gnoll slayer, huh? Very well. We can use all the help we can get against those bloodthirsty dogs. Right now, we offer a bounty of one moonstone per adult gnoll. You don't get paid for killng the pups. Bring back their fangs as proof but be sure to hand them to me one at a time so I don't lose count and shortchange you.
Now give Captain Tillin a Gnolls Fang for the following response:
Captain Tillin says 'Very good! One less gnoll the people of Qeynos need to fear. Here is your bounty as promised.
Your faction standing with Guards of Qeynos got better
You gain experience!!
You also get given a Moonstone as a reward. Note that your faction with Merchants of Qeynos, Antonius Bayle should also increase; Corrupt Guards of Qeynos and Circle of Unseen Hands should get worse. It didn't do so for me when I did this quest as I have done this quest too many times before I recorded it properly. This quest should be followed immediately with the McNeal Moonstones Quest in order to get best value from the Moonstones reward.