Shigeru Miyamoto, Nintendo's legendary game designer, and his fellow developers were tinkering with a "one-button control scheme" for Mario, where all a player can do is make Mario jump.
This dead simple idea became the crux of the company's new Super Mario Run, one of the most anticipated mobile-app games of the year.
"We found a great way to make an accessible Mario game and bring it to iPhone and reach a lot of people," Miyamoto said Thursday through his translator. "That's when we decided to make Super Mario Run."
He spoke about the origins of Mario and Zelda, as well as his creative process, in front of a small crowd of fans and media at Apple's SoHo store in Manhattan. The talk was timed just ahead of the December 15 launch of Super Mario Run on Apple's iOS devices.
By Friday, a demo version of the game will be available at all Apple Stores worldwide, an Apple spokesman said. Super Mario Run comes to Google's Android next year.
Super Mario Run may become a critical next step for Nintendo, which has struggled for years to maintain its relevance in gaming against Sony's PlayStation and Microsoft's Xbox, as well as a surge of mobile gaming apps. This year, it garnered some attention from Pokemon Go, though it's only partly involved in that game. Now, two more Nintendo mobile gaming apps -- Animal Crossing and Fire Emblem -- are on the way, which could provide the Japanese company with a big boost.
For Super Mario Run, Miyamoto said the company sought to create a game that's simple enough that a novice can pick it up easily, but with enough complexity that the many Mario super-gamers out there will also be pleased.
He said there will be a few new kinds of jumps and tricks in Super Mario Run that will give the game its own unique tempo and gameplay.
Asked where he sees the future of Mario, Miyamoto laughed then said: "It's impossible to know the future. I don't know what's going to happen in five years.
"I felt that if I want Mario to continue to survive as a character," he added. "Mario needs to evolve with technology and video games."