Inside each window of this advent calendar, you will find a Sudoku puzzle to solve. As well as classic Sudoku puzzles, the calendar also features other popular variants – such as Killer Sudoku, Jigsaw Sudoku, and more.

To give your December Sudoku-solving a purpose, we have created a points system. Your goal is to get as many points as possible by solving as many puzzles as you can. Correctly solved puzzles are worth 1, 2, 3, or 4 points, depending on their difficulty. Instructions are provided in English, German, Swedish, and Norwegian.