A US teenager won the top prize in a tournament for online video game Fortnite on Sunday.

16-year-old Kyle Giersdorf became a millionaire, scooping $3 million after winning the solo finals of the Fortnite World Cup in New York. The Pennsylvanian teen, who plays under the name “Bugha”, said, “Words can’t even explain it. I’m just so happy. Everything I’ve done, the grind, it’s all paid off.”

The big money prize is a sign of how booming popularity is fueling the rise of online gaming as a professional sport and attracting top dollar investments. At least 100 players took part at the Arthur Ashe Stadium in Queens. They were all chasing a share of the total $30 million prize pot.

Fortnite has also paid off for developer Epic Games. The Battle Royale-style game helped the software company reach a valuation of $15 billion last year.

Global revenues from professional video games competitions will hit $1.1 billion by the end of 2019 according to a report released earlier this year. That’s up 27 percent from the year before thanks to ballooning revenues from advertising, sponsorships, and media rights.