It's easy to see why Fortnite would grow so rapidly, and not just because it's free-to-play. Apart from its presence in the cultural zeitgeist (you know it's mainstream when Big Bang Theory, Saturday Night Live and World Cup players reference it), it's simply available on many more devices than it was at the start of 2018. Between the wider iOS release in April, the Switch version's arrival in June and the gradual expansion of the Android beta over the past few months, it would almost be harder to find a place where you can't play a round or two.

For Epic, the question isn't just whether it can keep growing its user base, but whether it can sustain that interest once growth slows down. It's trying, at least. There has been a steady stream of limited-time modes to spice up gameplay, and the company has poured $100 million into esports tournaments. The developers know they can't afford to rest on their laurels, and they're willing to spend a lot of cash if it keeps people coming back.