Roblox, the online gaming startup, is set to go public on Wednesday in an initial public offering that values the company at roughly $29.5 billion.

In January, Roblox said the company had raised over $520 million in financing ahead of the IPO. Meanwhile, the Roblox gaming platform has already made a millionaire of at least one of its young game creators.

A lot of teenagers spend their final year of high school preparing for college. But what Alex Balfanz did during his senior year ended up paying for college.

A 21-year-old student who began his senior year at Duke University in 2020, Balfanz is also the co-creator of the hit online video game Jailbreak. The game has been played nearly 3 billion times by hundreds of millions of people around the world, Balfanz tells CNBC Make It, and it's already made him seven-figure profits.

'Jailbreak just blew up'

In January 2017, just months before the end of his senior year at Trinity Preparatory School in Florida, Balfanz and a school friend released Jailbreak on Roblox, a popular online gaming platform with over 150 million users that also gives players a toolbox to create their own video games.

Balfanz says he and his pal (who prefers to remain anonymous) created Jailbreak, an "open-world, multiplayer cops-and-robbers game" after school and in their spare time.

Jailbreak, which is free to play but makes money when players buy new vehicles or weapons in the game, took off immediately. The game had 60,000 people playing concurrently on day one, and 90,000 by the next afternoon. (Jailbreak would eventually top 150,000 concurrent players, Balfanz and Roblox tell CNBC Make It.)

Balfanz says he made enough money to pay for all four years of his college tuition (which, based on the cost of attending Duke, is over $300,000), in just a couple of months.

In a little more than two years, the game made Balfanz and his partner millionaires, he tells CNBC Make It. They have easily cleared "seven figures" in overall profit, which they split evenly, from Jailbreak since it launched.

"I had no idea that it was going to ever get to the level it was," Balfanz tells CNBC Make It about the game's immediate, and lasting, popularity. "Jailbreak just blew up...."

A rendering of the hit Roblox video game "Jailbreak."

Jailbreak became among the most popular games on Roblox, a site with over 50 million different games to choose from.

"It was amazing. ...I had created something that people really cared about," says Balfanz, who adds that he remembers being rapt watching the number of players and how much money they were spending climb on his Roblox developer dashboard.

"I started making some money, and I remember going out and buying a drone, like the first day … I'd been wanting this drone for a long time," Balfanz says.

Other than buying the $1,000 gadget, though, Balfanz has mostly eschewed major splurges, opting instead to use the money to pay his college tuition and save for his future while also putting some money toward web servers and programming software to help him continue honing his coding skills.

Learning on Roblox

Balfanz and his high school friends had made a few different games on Roblox before Jailbreak. In fact, Balfanz says he started learning to write computer programming code when he was about 9, and Roblox was one of the first platforms where he honed his abilities.

In addition to offering millions of free games (with upgrades and in-game purchases), Roblox also offers a full suite of programming tools that allow users to create their own video games that they can launch publicly on the site in the hopes that, like Balfanz's Jailbreak, their games will one day be played by millions of people. The Roblox community currently includes more than 2 million creators, Roblox's chief business officer, Craig Donato, tells CNBC Make It.

Balfanz says he'd made "maybe a couple thousand" dollars in total from the previous games he made on Roblox.

"One of them was somewhat successful," he says. Launched in 2016, that game, called VOLT, was inspired by the Disney movie 'Tron' and has now been played nearly 9 million times.

"But everything really blew up when Jailbreak came about."

Balfanz and his co-creator started working on Jailbreak near the end of 2016 and spent roughly four months developing it. "I was coming home every day [after school] and working on it for the rest of the day," he says.

A rendering from the hit Roblox video game "Jailbreak."

What they came up with was a game where players can either opt to play as police or as prisoners. "The prisoners try to escape the prison and become criminals," Balfanz explains. "And from there they go into the city, start robbing banks, jewelry stores, trains, [they] fly helicopters, upgrade their vehicles, things like that. And then the other team, police, try to arrest them and send them back to prison where they have to escape again. And you just get this nice cycle of good versus bad, and there's a really fun game behind it."

Instant success

When the game first debuted and became such an instant success, Balfanz says, "I remember being overwhelmed by all the tweets and everything I was getting [from players]," he says. "Previously, I used to like reading everything that came my way, but now there is just so much information, so many tweets, so many people that I just couldn't handle it.

"Then I'd go to school and everyone knew about it, and everyone was asking me questions all of the time."

Between his classmates and the growing number of people playing Jailbreak, Balfanz says he and his co-creator were inundated with "thousands of features and suggestions." "All of these people had their own ideas, and it was really cool to see," he says.

Jailbreak's popularity has yet to wane in the more than two years since Balfanz's game debuted on Roblox. "It was our No.1 hit for quite some time," Donato says of Jailbreak, which is still one of only three Roblox games to be played over a billion times. It was also the fastest Roblox game to reach that milestone, doing so after roughly 14 months, according to the company.

Balfanz and his co-creator regularly look at the feedback that comes pouring in to implement ideas that will make the game more fun to play.

In 2019, Balfanz told CNBC Make It, "We finally added planes to the game, which is something people have been asking for since we launched." Balfanz is also busy adding new weapons and other upgrades that players can spend money on in the game, including missiles for the planes as well as other fun modes of transportation, like jetpacks and jetskis.

A rendering of the in-game action from the hit Roblox game "Jailbreak."

Looking ahead

Today, Balfanz is also busy studying computer science and statistics at Duke, where he says most of his fellow students are well aware that he's one of the creators of a game reaping seven-figure profits.

"For a while, I tried to keep it kind of on the down-low and never really talked about it too much," says Balfanz. However, word eventually got out around campus, and Duke's student newspaper even profiled him, which means that now, "pretty much everyone's heard about it," he says.

That's fine by Balfanz, who says he "definitely" plans to continue making video games, and the money he's making from Jailbreak means that he doesn't have to worry too much about landing a post-graduation job.

"I'm blessed financially with the opportunity to just be able to pursue entrepreneurship for the rest of my life," says Balfanz, who adds that he won't need to "go out and seek internships … I can just continue to create things that I find fun."

As far as his future career goes, in addition to continuing to create games, Balfanz looks up to tech titans like Tesla and SpaceX CEO Elon Musk. "I'm very inspired by Elon Musk and his ability to just, like, push boundaries wherever they are," Balfanz says. "I feel like my field is innovative, creative entrepreneurship. I love finding new things that haven't been done."

CORRECTION: This article has been updated to show that there are more than 50 million games available to play on Roblox.

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