Quest giver: Pablos
Experience: 2000
Gold: 3500
RC: 10
Speak with the thief's victims
Speak with Pablos
After defeating the Hydra in the Encampment, head back to Cassardis and talk to the innkeeper. Next, find the two NPCs named Aestella and Heraldo and talk to them. Report back to Pablos to update the quest. Agree to help them catch the thief at night.
Come midnight, stay still and wait until the thief makes his appearance. Give chase and try to stun him by using a melee attack. After stunning him, grab him successfully to capture him and complete the quest.
It's easier to wait across from the Inn until he opens the door, he will just stand there for a few seconds and you can run up and grab him.