More than 100 million people now play League of Legends every month, the co-founders of developer Riot Games told reporters this week. That’s as many monthly users as those boasted by streaming music service Spotify, and it’s more than the 83 million worldwide subscribers to streaming video giant Netflix. The gaming developer last revealed user numbers more than two years ago, at which point 67 million people were playing the game on a monthly basis.

As Fortune has reported, League of Legends has seen its user base increase rapidly as more and more gamers flock to the growing eSports market, which is expected to approach half a billion dollars in global revenue this year alone as tournaments continue to move into the mainstream. ESports teams compete around the world in matches with huge followings and millions of dollars at stake in prizes and sponsorships.

Major media companies like Walt Disney’s ESPN (DIS) and Time Warner’s Turner Broadcasting (TWX) have also jumped on the eSports bandwagon, where League of Legends is one of the biggest draws, filling stadiums with tens of thousands of fans. Last year’s World Championship averaged 4.2 million concurrent viewers on TV and online.

Riot Games co-founders Marc Merrill and Brandon Beck talked to the Los Angeles Times on Tuesday about their company’s 10th anniversary and the ever-expanding popularity of League of Legends—which they said “has become a shared language and passion” in the gaming community. While the game is free to download and play, Riot Games makes money off players’ in-game transactions. The company, which is owned by Chinese social networking giant Tencent, has stayed mum on revenue it gets from its sole videogame title, various reports suggest that Riot Games easily pulls in more than $1 billion per year.