The diminutive dynamo departs Paris with three golds and one silver medal, taking her career tally to 11 Olympic medals. She has seven golds.
The 27-year-old American became just the third woman to win two Olympic all-around titles and the first to do it at non-consecutive Games.
Biles was 19 when she dazzled at the 2016 Rio Games, winning gold in all-around, vault, floor exercise and team events.
She arrived at the pandemic-delayed Tokyo Olympics with superstar billing and history in her sights, but withdrew from most of her events as she struggled with the disorienting mental block that gymnasts call the "twisties".
Hailed by many as a mental health trailblazer but criticised by a few as a quitter, Biles took a two-year break, only to return better than ever.
In the French capital she laid the ghosts of Tokyo to rest, leading the United States to a resounding team gold.
She became the oldest woman in 72 years to win Olympic all-around gold, shaking off a disappointing uneven bars routine that had her trailing in the final to edge Brazilian Rebeca Andrade.
She followed up with a stunning vault victory, unleashing her signature Yurchenko double pike -- now known as the Biles II -- to virtually lock up the gold on her first vault.
Biles was unable to grab another gold on the final day of competition, finishing out of the medals in balance beam and taking silver in floor exercise.
Nevertheless, she departs Paris with a jaw-dropping tally of 41 world and Olympic medals -- 30 of them gold.
Redemption
The American, who was just 16 when she started that collection with her first all-around world title in 2013, confirmed her status as a must-see sensation.
Hollywood A-listers, sports stars and billionaire entrepreneurs flocked to Bercy Arena, along with legions of young gymnastics fans thrilled to see their idol.
Biles suggested the glamorous turnout was a celebration of an Olympics freed of the Covid restrictions that made Tokyo a sterile affair.
Teammate Sunisa Lee knew better.
"I would have to say honestly, Simone, I feel like a lot of it has to do with you," she said.
Even before she and her teammates embarked on their Paris "Redemption Tour", Biles was a massive draw.
More than seven million Instagram followers basked in the fairytale photos of her wedding to NFL player Jonathan Owens, who received special dispensation from the Chicago Bears to miss a few days of training camp to watch her in Paris.
Pop icon Taylor Swift signalled her approval when Biles chose a phrase from Swift's "Ready For It?" to kick off her floor routine.
Tumultuous
Biles's ascent has featured as many twists as one of her signature tumbling moves.
Tokyo capped a tumultuous period that included Biles's revelation, in 2018, that she was among the hundreds of gymnasts who were sexually abused by former Olympic team doctor Larry Nassar.
She was a vocal critic of USA Gymnastics and the United States Olympic and Paralympic Committee over their handling of the scandal and a leading voice calling for their accountability after Nassar was convicted and imprisoned.
The gymnast who called 22-year-old teammate Aly Raisman "grandma" in Rio is now an elder stateswoman, and her more than 10 years of dominance have redefined a sport that now features five signature skills named after her.
"She's the most talented athlete I've ever worked with and so we just knew if she could get her mental game as well as her physical game, then she would be close to unstoppable," said Cecile Landi, who coaches Biles with husband Laurent Landi.
'Proud of Simone'
Biles pays meticulous attention to her mental health, even meeting long-distance with her therapist during the Games.
Her path has also been made easier by the supportive environment at World Champions Centre, the Texas gym owned and operated by Biles's parents, Nellie and Ron.
The couple, in actuality Biles's grandparents, adopted Biles and her sister Adria after they ended up in foster care, their biological mother unable to care for them because of substance abuse struggles.
Biles, who was honoured with the Presidential Medal of Freedom in 2022, said she is as proud of her journey as she is of her athletic feats.
"Just to see where I've grown even from Tokyo and even from the 19-year-old from Rio is amazing," Biles said.
"Because I never thought I'd be on a world stage again competing. So just proud of Simone for putting in the work and never giving up."