Ulok is a Convicted murderer. He was scheduled for execution until the day of his sentencing, his Dragonmark manifested. It ranges from the eyebrows over the scalp to his waist. He has a sense of smell that can identify Race, Age, health, and according to Rast, education.
He prefers close combat and the chase. According to Baalzephax, the guards he has (who would be no challenge for him to overcome) are there to tempt him.