In the mood to challenge your brain? Here are some printable sudoku puzzles that are sure to make you think hard. Sudoku puzzles aren’t easy, but with a little practice and some helpful sudoku ...

Unveiling 'World's Hardest Sudoku Book Vol. 2': 200 New Puzzles to Challenge Enthusiasts, Continuing the Bestselling Legacy. It has been a long journey, but I am confident that these puzzles will ...

Finland based mathematician, Arto Inkala, has specially created a Sudoku to rival his World’s Hardest ‘Al Escargot’ puzzle produced in 2006. The puzzle is waiting for anyone who wants to test their ...

Could this be the toughest sudoku puzzle ever devised? Number cruncher Dr Arto Inkala has created this new challenge to rival the AI Escargot grid he drew up in 2006 – widely regarded as the ...