Chinese tech and video game company Tencent is working with subsidiary Riot Games on a mobile version of League of Legends.

As reported by Reuters, which claims to have spoken with "three sources with knowledge of the matter," the mobile version of the popular MOBA has been in development for over a year, but probably won't see the light of day until 2020 at the earliest. 

League of Legends earned an estimated $1.4 billion in 2018, and while that's hardly a paltry sum, it's significantly less than the $2.1 billion it amassed throughout 2017. 

A mobile version of the game could help arrest that revenue slide by giving Riot and Tencent access to new players, and perhaps presenting new monetization opportunities. 

"League of Legends is not doing as well as it used to and so Riot badly needs a new way to monetize the game, especially considering that it is Riot's only game," said Newzoo analyst Gu Tianyi, speaking to Reuters. 

While there have also been suggestions a mobile version of League could make the title more viable in Asia and help with Riot's esports efforts, Tianyi claimed it might still struggle in the lucrative Chinese market due to the success of Tencent's other mobile MOBA, Honor of Kings -- which had an estimated 140 million active users in March.