Boasting over 45 million players and the Twitch record for most live viewers on a stream, third-person shooter Fortnite Battle Royale has taken the gaming world by storm. But given that it uses a free-to-play model, how is it avoiding the controversy that often surrounds in-game microtransactions?

E-sports is a well-established spectator sport, and Nike is the latest brand to get on board, with sponsorship of China’s famed League of Legends Pro League. The sportswear giant has followed in the footsteps of Puma and Adidas, tapping into people's desire to engage with unconventional sports.

Not long ago, it was inconceivable that video games would be anything more than a niche pastime, let alone a path to a lucrative career. Yet e-sports now attract millions of fans and major brand sponsorships. How did they come to rival to traditional sports? And can they achieve mainstream success?

Mountain Dew has created a soft drink range especially for gamers, named Game Fuel. As the world of e-sports gains more public attention, the product line plays up the idea that being a professional gamer can be just as demanding as being a professional athlete.