Last October, software developers at Riot Games in Santa Monica fielded an unusual request. Like other videogame makers, Riot’s success depends on its ability to make games that are compulsively playable, like its global hit League Of Legends. But Tencent, the Chinese tech giant that owns Riot, needed a way to force some of its most enthusiastic customers to play less.
While it has owned a controlling stake in Riot since 2011, Tencent has generally been hands-off when it comes to the company's products. But facing increasing pressure from Chinese state media and regulators over its role in a supposed epidemic of videogame addiction, Tencent needed a way to track how much time individual gamers in China spent playing League Of Legends – and kick out minors who exceeded two hours per day. If Riot engineers didn't supply an “anti-addiction system” for League Of Legends, they might lose access to the Chinese market altogether.