He was described as a big fellow who had wide hands and stubby fingers.
The thieves Rheena, Shreth and Loor made the mistake of picking Breaker-Jon as a target. The man snatched Loor's hand and send him flying, then dragged Rheena into an alley. Dorin Rav followed them and threatened Breaker-Jon with knives. Before letting them go, the man told Rheena to pass on a message to her employer not to trespass on their territory, presumably meaning that of Urquart's gang.