Duplantis eased through Saturday's qualifying and began today's Final by taking the opening height of 5.55m, sailing over at his first attempt as he settled into the hot an humid conditions in the Japanese capital.
The 25-year-old then opted to skip the next height of 5.75m, at which his closest rival Emmanouil Karalis and former Olympic champion Renaud Lavillenie entered the competition. Duplantis rejoined the competition to sail over 5.85m with ease.
The Swedish star then made a statement by clearing 5.95m at the first attempt before any of his rivals managed to clear 5.90m, which again he chose to skip.
That put Karalis under pressure - the Greek failed twice at 5.95m before pulling a clearance out of the bag on his third and final attempt. He took that momentum into clearing 6.00m at the first attempt, which Mondo matched immediately.
Those clearances at 6.00 descimated the field, with no other competitor unable to clear that height, as Australia's Kurtis Marschall took bronze ahead of Sam Kendricks of the United States, having cleared 5.95m with fewer failures than the American.
Duplantis then cleared 6.10m to maintain a perfect record, and though Karalis missed at the same height, he made the bold decision to raise the bar to 6.15m. The European Indoor champion failed marginally, before Duplantis went clear yet again.
Karalis went straight to 6.20m, but a first failure at that height was his third in a row, meaning he collected the silver medal, his first silverware at the World Championships.
With a third World Championships gold medal confirmed, the only question was whether or not Duplantis would attempt another world record.
In front of a capacity crowd which was staying just for "the Mondo show", Duplantis set the bar at 6.30m for the first time in pole vault history, but he failed at his first attempt. On his second attempt, Duplantis thought he had it, before the bar wobbled and fell agonisingly to the floor.
But on the third and final attempt, with the crowd roaring him on, Duplantis delivered, clearing 6.30m - a height previously thought impossible to break - to set the world record for the 14th time, and win Sweden their first gold of these championships.