A British teenager whose obsession with video games caused years of arguments with his despairing mother has won almost £1m and become an overnight star after finishing second in the hugely popular Fortnite World Cup.

Essex schoolboy Jaden Ashman, 15, competing under the name Wolfiez, finished runner-up with his Dutch team-mate Dave John (Rojo) in the duos event, landing a $2.25m (£1.8m) prize fund, which they will split.

Ashman was one of several UK gamers to fly to New York to take part in the tournament where 100 competitors, many aged between 12 and 16, battled it out for a total prize pot of $30m – the largest ever for an esport event.

While many of those taking part were professional Fortnite gamers with legions of fans, Ashman was a relative unknown with only a few thousand followers on social media. The teenager put his success down to the many hours he has devoted to Fortnite since the day it came out in September 2017, sometimes playing it for up to eight hours a day.

“Me and my mum, we clash quite a lot,” Ashman told the BBC. “She didn’t understand how it worked, so she thought that I was spending eight hours a day in my room just wasting my time. So now that I’ve proved to her I can do stuff, I’m really happy.”

His mother, Lisa Dallman, said she once threw out an Xbox after an argument but now accepted his career choice as a professional esport player. He got into gaming watching his uncle play the shooter Gears of War, before getting his own Xbox aged six.

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

Dallman told the BBC: “If I’m honest with you, I’ve been quite against him gaming. I’ve been more pushing him to do his schoolwork. I’ve actually thrown an Xbox out, snapped a headset – we’ve had a nightmare.”

The 15yr old millionaire Fortnite player Jaden Ashman and his mum Lisa Dallman. He came second with his teammate on the duos and will split $2.25m! His mum says accepting him as an e-sports player has been very hard and she’s even thrown out an X-Box in past!! #FortniteWorldCup pic.twitter.com/UCUqGzUOLW — Joe Tidy (@joetidy) July 27, 2019

Ashman nearly missed the tournament entirely. He had problems securing a visa for the US flight and, in a mishap that would get laughed out of a classroom, the dog ate his birth certificate.

“This is not a joke – this actually really did happen,” said Dallman. “And then my work messed up my wages, so three things went wrong before we started heading here so I knew we were on an even keel and everything was going to go right.”

Asked how her son might spend the prize money, she said: “I think Jaden’s not really a materialistic person. He will have a lifetime supply of Uber Eats, and I think that will do him, to be fair. Just sitting there playing video games and eating takeaways, Jaden would be in his element.”

The duos winners, Emil Bergquist Pedersen from Norway and his Austrian partner, David W, who play as Nyhrox and Aqua, took home a total of $3m prize money.

The $3m solo prize was won on Sunday night by Kyle “Bugha” Giersdorf, a 16-year-old from Pennsylvania, in what is believed to be the biggest winnings in esports history.

The teenager exhaled, shrugged, laughed and fist-bumped as he was crowned the world champion, telling fans: “I’m just so happy. Everything I’ve done – the grind – it’s all paid off. It’s just insane.”

More than 100 finalists took part in the event, trimmed down from about 40 million who attempted to qualify for the tournament.

With more than 250 million players, Fortnite: Battle Royale has become one of the most popular video games in the world since its launch in 2017. Thousands of fans attended the three-day final in New York with many more watching online. There were no women among the finalists, most of whom were under the age of 20.

Another British teenager – Kyle Jackson, a 14-year-old from Sidcup in Kent – won $150,000 for finishing 13th in the solo competition after last year becoming the youngest professional Fortnite player in the world.

Jackson, who goes by the online moniker Mongraal, is a member of professional gaming team team called Faze Clan. “It really is amazing to do something like this from a young age,” he told Sky News. “To be able to do what you want to do and earn money from it, it is the main goal in life.”