Nikoli Publishing, the premier Japanese puzzle and game company, holds the trademark on Sudoku in Japan, and supplies 100 percent of the puzzles published in Japanese newspapers and magazines. Maki Kaji, the "Godfather of Sudoku," is president of Nikoli and is credited with giving Sudoku its name.

Master puzzle maker Kazuyuki Yuzawa (aka "Mr. King") has been making mazes for 30 years. Jimmy Goto, editor in chief at Nikoli, explains, "There are many puzzle makers in the world. Among them, Mr. Yuzawa occupies the throne, so people call him Mr. King of Mazes." Yuzawa is an electrical engineer by day, so the time he has to create his masterful mazes is limited - there are fewer than 150 puzzles created by him in the world.