But for Marc Merrill and Brandon Beck, founders of Riot Games, the number is a "trailing indicator", a reaffirmation of their player-first development approach rather than a key indicator they discuss internally.

Early on in the online, team-sports-meets-fantasy game's development, the pair realised they'd need to raise venture capital to produce the kind of experience they envisioned, freeing them to run the service more like a sport than a traditional video game.

But their first realisation about just how sport-like the game could be came two years after its 2009 launch.

"League's competitive scene had evolved essentially a ladder type of system, which begged for a play-off," says Beck.

"There needed to be a top level of play, and that sort of culminated with a tournament that put the best teams in the world together for our first competitive season, at a LAN party in Jonkoping, Sweden.

"We had about 100 folding chairs at this event ... we were excited about it. But what blew us away is that 100,000 players tuned in on the stream [simultaneously], which at the time was completely unprecedented."

Beck says the success of that event gave them confidence to dream bigger: high production sports broadcasts featuring League of Legends.

In 2012 the Season 2 World Championship prize pool had grown from less than $100,000 to $2 million and was viewed online by 8.2 million people - both figures that broke records for e-sports at the time.

"[The event] was held at the Galen Centre, which is the USC basketball arena in LA, and that was the first time Riot held an event in a big arena ourselves," Merrill says.

The momentum never slowed, and in 2015 the Season Five World Championship finals in Berlin were watched by 36 million unique viewers.

Now in its sixth year, 2016's championships begin on September 29 and will take place in the US.