It started with an extra Taylor Swift CD that needed to be given away.

Snowglobe Allie, a Taylor Swift fan who asked not to be identified by her last name for safety reasons, had an extra copy of Swift's latest album, Midnights, that she had picked up when she attended her concert at MetLife Stadium in May.

While experiencing what she described as post-concert sadness, Allie went on X, formerly known as Twitter, and tweeted out from her account that she wanted to give away the album in a new and interesting way.

With Swift typically wearing different outfits each night of her concerts and playing different songs, Allie created a ballot where people could guess what outfits and songs they thought Swift would have.

"I came up with like, 'Oh, we can do this fun little guessing game for a one-time giveaway.' And then people enjoyed it so much, they asked me to do it again, and then again, and here we are now," she told USA TODAY.

And so, the concept for Allie Fantasy Swiftball was born.

Now, 21 games and over 18,000 participants later, the game is captivating Swifties all over the world who can't physically be at the concerts.

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Swift fans fill out ballots, watch livestreams to participate

People playing Allie Fantasy Swiftball go to Allie's X account the night of the concert and fill out a Swiftball ballot using a Google Form that she creates each concert night.

Fans go through the ballot and enter their predictions for Swift's outfits and surprise songs throughout the concert. Each correct prediction earns the user points. The fan with the most points at the end of the night wins.

With 24 total questions but multiple outfit options in each question, it's difficult to get a perfect ballot, which is worth 113 points.

People can change their ballots and predictions up until right before Swift comes on stage. As the concert begins, fans will tune in on livestreams being run by people at the concert so they can watch with the people physically there and see how their ballot is doing.

Winners receive prizes, that have been donated by other fans, Allie said.

The first two nights of Swiftball had prizes provided by Allie herself. After that point, she tweeted out that it wouldn't be feasible for her to purchase prizes for winners each concert night. That's when the donations started.

"Once one person donated and I mentioned that people were sending prizes, it's like the floodgates are open," she said. "My DMs are always flooded with people being like I have this that I would love to donate, or I would love to donate stuff from my Etsy, or I have old merch that I don't use, or I accidentally ordered this in the wrong size, have this as a prize."

Swift closes out the first leg of her U.S. tour on Aug. 9 in Los Angeles, and Allie said they have at least six prizes each night ready for winners to receive.

"Just the fact that everyone is so so generous and wonderful and lovely, really it's mind blowing to me," she said.

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'I thought it was going to be a one-time thing': Swiftball expands

For the first couple of weeks, Allie was running the game by herself. Now, she and six other people work as a team to put the virtual game on each concert night.

The team members are all volunteers and have different roles in Swiftball, whether it's creating different digital patches that the fans receive when they participate in the game or looking through the ballots and counting up the points.

Allie said every person who joined the team approached her and offered to help her in some way, and then never stopped.

Even the naming of the game happened naturally. Erin Cuomo accidentally coined the game as Swiftball on X after she tweeted she wanted to keep playing the game, even if Allie did not provide prizes.

"It was just this silliness and sunshine that it really brought to Twitter, and I jokingly responded, 'Allie's Fantasy Swiftball is the only thing that's getting me through this week,'" she told USA TODAY.

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For Raghav Kalra, joining the Swiftball team was an easy decision. He told USA TODAY that he had been playing the game previously and was excited to grade the ballots, which use a coding system Allie had set up to track points.

Kalra said the biggest part of his job is checking through entries that fans write in manually, like the guesses about Swift's surprise songs.

"I still go and manually check that every single person who had that particular entry for the surprise song or anything close to it, which can be granted as an acceptable response, does get points. So, if it's a popular guess, it's kind of a bad night for me to check thousands of people manually," Kalra said. "Even though we do code for it, it's a double-checking process. I think that's definitely the most intense part of the night."

Nearly 18,000 people played the game Thursday night, which set a record for a single game's participation, Kalra said.

The other important roles include a badge designer who creates virtual badges fans can earn while playing Swiftball, and outfit experts who help determine what outfit Swift is wearing when she comes out during each set of her concert, and whose night can be completely dictated by the quality of the livestreams.

Swifties find community, engagement through Swiftball

Above all the prizes and playful competition, the best part of Swiftball is the community it creates for people who aren't at the concerts, Kalra said.

"It's genuinely becoming such a big part of being a Swiftie, and I'm absolutely overjoyed by the fact that some people get to enjoy The Eras Tour from home, even though they're not there in person," Kalra said. "I think that's a beautiful thing."

Additionally, Swiftball is an accessible community for all fans, including people who may be disabled or have chronic illnesses such as herself, said Jacqueline City, a creative director with the team.

"We all have something to do that doesn't involve me going out, especially when I'm feeling sick or don't have the energy to go out and do these things in person," City said. "...To live through the eyes of other people and still feel so involved and feel like we have this topic that we're all so excited for, it's really a sense of community that I haven't had in a while. And I think that a lot of people feel the same way."

Swiftball might have even caught the attention of Swift herself. Fans think Swift might have slyly acknowledged the game during her concert in Los Angeles on Friday night.

"To anyone who's been following this tour like it's your favorite sport, I love you so much," Swift said during a speech in her Evermore set.

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