Last night, a US teenager who goes by the name Bugha – real name Kyle Giersdorf – became the Fortnite World Cup Champion. The 16-year-old beat 99 other players in the brightly coloured Battle Royale game, running, building and fighting his way to a $3m (£2.4m) victory.

The competition began months ago, with waves of qualifiers being selected in weekly online play-ins. A total of 40 million people attempted to qualify for the World Cup, the first esports event of its kind for the mega-hit Fortnite, one of the world’s most popular video games. The 100 who made their way to New York this weekend represented 30 different countries.

Once there, they faced off in six rounds of the game’s last-man standing battles, scoring points for eliminating others or staying alive for as long as possible. A pro player for the esports organisation Sentinels, which fields players in Hearthstone and Apex Legends tournaments as well as Fortnite, Bugha pulled ahead in the very first round, racking up nine eliminations and surviving all the other players.

The final of the 2019 Fortnite World Cup took place at Arthur Ashe stadium at Flushing Meadows in Queens, New York. Photograph: Jason Szenes/EPA

Though his performances in future rounds were less attention-grabbing, his consistency meant that he stayed in first place throughout. In the sixth and final round he stayed alive until the top 10, eventually falling, but already smiling because he knew no one could catch up to his points lead. He ended up with almost double the score of the second-place competitor.

Quick Guide What is Fortnite? Show What is Fortnite: Battle Royale In short, it's a mass online brawl where 100 players leap out of a flying bus on to a small island and then fight until only one is left. Hidden around are weapons and traps, and players must arm themselves while exploring. When was it released? Fortnite started in July 2017 as a four-player cooperative survival game, but the game's developer, Epic, noticed the huge success of PC title PlayerUnknown's Battlegrounds (PUBG), which pits 100 players against each other, and decided to release a new version. How much does it cost? The game is free and players are able to unlock new items as they progress without paying anything. A Premium Battle Pass gives access to exclusive clothing and items. However there is an in-game currency, V-Bucks, which players can use to buy additional custom gear. It is how this currency is paid for that has become the centre of a dispute between Fortnite's makers and Apple and Google. Why is it so popular with kids? It's free, it's fun, and it has a very silly, offbeat sense of humour. While PUBG has a serious, realistic visual style, Fortnite: Battle Royale has very bright, almost cartoon-like graphics, as well as loads of ridiculous items and costumes, such as space suits and dinosaur outfits. Players can pull a variety of dance moves, and team up with a friend to compete as a duo or a squad. Participants can chat as they play using headsets and microphones. Is there violence? And is it addictive? Although Fortnite is a multiplayer shooter, it does not depict bloody violence. It takes lots of enjoyable gameplay concepts from more mature shooting games but places them in a non-threatening, non-realistic world. In terms of addictiveness, Fortnite contains nothing that makes it different from other action video games. It's more that the game contains many different elements – nice visuals, good shooting mechanics, an interesting building component and lots of support and interest from YouTubers – into one package that is free to download. Photograph: fortnite

The American competitor described how he was feeling in a post-match interview. “I’m just so happy. Everything I’ve done, the grind, it’s all paid off.” His family was in the stadium to watch and congratulate him. So, too, were approximately 16,000 other attendees, with millions more tuning in online.

Because each Fortnite match starts out with 100 players, they can be difficult to follow as precisely as more straightforward competitive games. Matches usually begin slowly as players drop on to their favourite spots on the map and gather materials, guns, and stranger additional items like a hamster wheel for quickly travelling around or a shadow bomb that makes you temporarily invisible.

After a short time, a “storm” appears on the map, forcing players to move into a more condensed area. As the arena becomes smaller and smaller, the action ramps up, beginning with scraps between two people or small groups, and ending with an all-out brawl with dozens of competitors packed into a tiny space. When only two players remain, a tense 1:1 battle determines who will get the all-important victory royale.

Many viewers of the Fortnite World Cup had favourite players that they supported throughout the tournament. The most popular competitor at the World Cup was likely Turner Ellis Tenney, better known as Tfue, who regularly broadcasts his matches to a dedicated community. Playing Fortnite is already his career, both as a competitive player in tournaments and as a streamer on Twitch, entertaining his fans on a daily basis.

But many of the 100 competitors were ordinary teenagers, who practise on their home computers or consoles.

The final of the Solo competition at the 2019 Fortnite World Cup. Photograph: Johannes Eisele/AFP/Getty Images

Sixteen-year-old Bugha represents the average age of a competitor, while others, including fifth-place finalist Thiago “King” Lapp from Argentina, were as young as 13. They were competing for a slice of the World Cup’s $30m (£24m) prize pool, currently the biggest in esports history – and the same amount awarded to teams in the recent women’s football World Cup.

One 15-year-old British player, Jaden Ashman, took home over £1m by placing second with his partner in the duos version of the competition on Saturday. He told the BBC that he would probably save half of it and put “quite a lot of it into a house and my family”.

His mother admitted that she had been “quite against his gaming”. But with Ashman, King, Bugha, and others taking home life-changing amounts of money, and every competitor in the final 100 earning at least $50,000, it’s clear that professional gaming can be an incredibly lucrative career for those few who are lucky, talented, and hardworking enough to make it.