An art as much as it is a sport, parkour's urban ethic is one of bold, practiced risk-taking. Now its adherents say it is having to fight against encroachment by powerful interests.

Rooftops & Alleys: The Parkour Game is a sport game focused entirely on the experience of parkour and freerunning—which is to say it's not also a shooter or a game about stabby people in hoods.

However, parkour’s origin is in France, and that is why the Assassin’s Creed-esque torchbearer is showing off the moves during the Parade of Athletes on Friday.

It’s a Monday night and members of the Hong Kong Parkour Association have gathered in the remote park one stop from the end of the Tsuen Wan MTR line. (Kowloon Park is also a popular training spot.) ...