New York (CNN) As the two teenagers from Europe set down their mice and took their hands off their keyboards, they turned to each other in disbelief: They had just won $3 million playing a video game.

Players have flown from all over the world to compete at the first ever Fortnite World Cup, a large sporting event at New York's Arthur Ashe tennis stadium with $30 million in cash prizes. The epic tournament will determine this year's best Fortnite solo player Sunday and has already found this year's best duo team.

Fortnite is a game that involves 100 players dropping onto a virtual island and fighting to be the last one standing while a health-point draining storm brews in the background.

Aqua, 17, and Nyhrox, 16, lived through that storm.

Fans and announcers were stunned late Saturday when Aqua and Nyhrox, two underdogs, beat out 49 other teams, many from larger, more funded organizations.

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