At home, while commuting, during lunch hours...people around the world
are eagerly working on Sudoku puzzles whenever and wherever they can!
Created in the United States, these intriguing conundrums were
originally called Number Place puzzles. Their recent rise in popularity
began in Japan, where the name translated as sudoku. Here we've
indicated the skill level necessary to complete each sudoku book in this
series in the same way Japanese karate levels are ranked: by different
colored belts. This is the Black Belt volume, filled with puzzles that
will provide a sly, absorbing test for even the best, most proficient
experts.
It's impossible to complete only one sudoku at a time, because solving
them is habit-forming!