Chang Wai-San, known as "Mr. Chang," is the boss of a Thailand branch of the Sun Yee On Triad.
Most of Chang's background is unknown. Before joining the Triad, Chang was in law enforcement, presumably in Hong Kong. His departure from his previous job into the Triad is tantamount to betrayal, as it caused the deaths of some of Chang's former co-workers.
It is also not known if Roanapur was Chang's original post or how long he has been in the city, but Chang's residency in Roanapur predates that of the other crime lords. He fought Balalaika in 1993 when Hotel Moscow came to the city in a battle so intense that it nearly destroyed the city. The Italian mafia and Columbian cartel arrived at some time after that battle.
Like Revy, he is adept with dual-wielding pistols in a fashion similar to that of gun-fu, and favors a pair of Beretta 76 pistols. The grips of these weapons are inscribed with two Chinese symbols (天帝), meaning "Heavenly Emperor."