Although the initial concept for the game had been scrapped, the development of that original two-player cooperative prototype inspired all the innovative gameplay of Super Mario Bros. 2, Tanabe said. “Picking up blocks was the same thing as pulling out vegetables from the ground,” he said. By the same token, picking up the other player and throwing him turned into picking up enemy characters. Doki Doki Panic was actually part of a deal with the Fuji corporation, in which Nintendo would produce a tie-in videogame for a media-technology expo called Yume Kōjō, or “Dream Factory.” The mascot characters invented for this expo were the stars of the game. “I remember being pulled over to Fuji Television one day, being handed a sheet with game characters on it and being told, ‘I want you to make a game with this,’” Tanabe said. Released in 1987, Doki Doki Panic was one of the biggest hits on Nintendo’s Disk System, a floppy drive that worked with the Japanese version of the NES. Since this hardware was not released in America, many Disk System games were ported to standard game cartridges for US release. “Because we had to make this change, we had the opportunity to change other things” about the game, said Tanabe. “We knew these Fuji TV characters wouldn’t be popular in America, but what would be attractive in America would be the Mario characters.” Tanabe’s team made many improvements to the original for its American debut, adding more enemy characters, throwing in some visual nods to the Mario games and greatly enhancing the animation and sound effects. Because one of Mario’s most notable features at the time was his ability to grow and shrink when he ate magic mushrooms, this was added to the game. But the implementation was not without its issues. “When the characters got shrunk down to a smaller version of themselves, it was easy to sneak through parts of the level that you weren’t supposed to go through, so we made their heads bigger so they would get caught on those things,” Tanabe said. The enhancements to Super Mario Bros. 2 were so great that the game was eventually brought back to Japan, retitled Super Mario USA.