Evil Sudoku, sometimes called Master Sudoku, represents the highest level of difficulty in Sudoku puzzles. These 9×9 grids are designed for expert solvers who have mastered easy, medium, and hard puzzles and are ready to push their logical reasoning to the limit. Unlike simpler puzzles, evil Sudoku offers very few starting clues, demanding advanced techniques, patience, and a deep understanding of Sudoku strategies.
While evil Sudoku can be daunting, many enthusiasts find it to be the most rewarding way to exercise their minds, improve concentration, and develop advanced problem-solving skills.
If you want to practice before tackling evil puzzles, try our hard Sudoku or medium Sudoku challenges.
The rules of evil Sudoku are the same as classic Sudoku: fill the grid so that each row, column, and 3×3 box contains the numbers 1 through 9 exactly once. The challenge comes from the scarcity of given numbers—sometimes as few as four clues to start! This means you’ll need to rely on sophisticated logic and advanced tactics rather than simple elimination.
A good starting point is to focus on the regions (rows, columns, or boxes) with the most given numbers, as these are often the easiest to make progress in. As you fill in more cells, new opportunities for deduction will open up across the grid.
To conquer evil Sudoku puzzles, you’ll need to go beyond the basics and use a variety of advanced strategies, including:
Explore our Sudoku techniques and strategy articles to master the skills needed for evil Sudoku.
If you’re solving on paper, consider using different colors or symbols to track candidates and highlight patterns. Online, take advantage of features like notes, undo, and hints to experiment and refine your approach.
Many of the techniques you’ve learned from medium and hard Sudoku—such as scanning, cross-hatching, and block interactions—are still essential at the evil level. However, evil Sudoku will require you to combine these methods and think several steps ahead. Practicing with medium and hard puzzles is a great way to prepare for the ultimate challenge.
Playing evil Sudoku online offers unique benefits:
Regularly tackling evil Sudoku puzzles is an excellent way to sharpen your mind, boost your concentration, and develop advanced analytical skills. With dedication and practice, you’ll find yourself mastering even the most fiendish grids—and enjoying every step of the