This addictive game became a national phenomenon in Japan in the early 90s. A decade later, it escalated into a worldwide craze.
Many of you are familiar with the game, but maybe you don't know where it comes from.
The brainteaser was first made popular by university dropout Maki Kaji. The Japanese national stumbled upon a similar puzzle in America called the Number Place in 1984. The original version was fun, but difficult. Kaji decided to take it back to Japan, and gave it a makeover.
That was the beginning of his puzzling career. He founded his own puzzle company called Nikoli, and started publishing a quarterly magazine in Japan featuring a variety of mind-exercising puzzles.
But Sudoku is only one of the weapons in Kaji's arsenal. This time, he is bringing another brainteaser - Shikaku - to Hong Kong.
Unlike Sudoku, Shikaku is not an adaptation of another game. "Shikaku was invented by our staff in 1989," Kaji says.
Shikaku means a cube in Japanese. It comes in a grid similar to Sudoku; they both have numerical hints and mysteriously empty boxes. But instead of numbering boxes, this game is about dividing them.
Each number indicates the number of empty boxes that should go around it. To complete the puzzle, you need to divide those boxes according to the numbers given, and avoid any overlaps.
To make their puzzles more diverse and engaging, Kaji's company creates every puzzle manually. This is an immense challenge because Nikoli is a small company with only about 20 workers. Of these, only half take part in the puzzle-making process.
To cope with the monstrous amount of puzzles it needs to publish every month, the company needs a bigger collective mind - their readers.
"We have about 1,000 readers who are puzzle makers," Kaji says.
Nikoli encourages readers to submit their puzzle ideas and designs.
About 10 puzzle editors will collect them, and make the call to decide which stays and which goes.
Sometimes, the good ones will get published straight away. Other times, editors will combine puzzles to create a new, more appealing one.
Many scientists say these brainteasers can train your brain and teach you how to think logically. Even though it is true, this is not what Kaji intended when he started the company. "Mind puzzles are for people's entertainment," he says. "They are people's pastimes."
Nikoli's editors follow a set of rules when creating puzzles. Because their goal is to entertain people, each puzzle comes with differing degrees of difficulty. But they must be neither too difficult nor too easy. "Surprises and twists are also important," Kaji says.
With everything going digital these days, Kaji will be happy if his puzzles appear on mobile phones and tablets one day.
But he expects his puzzles to stay in the print media, which is still the most accessible and affordable medium these days.
From today until June 8, Young Post will be running one Shikaku puzzle every Tuesday and Friday. Turn to page 11 to have your very first taste of this brainteaser now.