Scoundrel's Blood by Gabor Cebe and Viktor Csak

As one of the top thieves in the city of Cyrdain you lead a comfortable life. Still, you await the day of your Master Exam eagerly. A successful Exam would mean fame, prestige and wealth, not to mention the privilege to sit among the greatest of the Guild. It's everything you ever wanted.
However when the day finally comes, you realize that it will take every trick you ever learned just not to fail, and it might take even more to survive the aftermath...