What Is Samurai Sudoku
Samurai Sudoku is five standard 9x9 Sudoku grids arranged in an overlapping pattern. One grid sits in the center. Four more are placed at the corners, each overlapping the center grid by one 3x3 box. The result is a massive puzzle with 369 cells total (81 per grid minus the 36 shared cells).
How the Overlap Works
The four corner grids each share a 3x3 box with the center grid. This means those shared boxes must satisfy the rules of two different grids at the same time. A number you place in a shared box affects candidates in both grids. This overlap is the key to solving Samurai Sudoku.
Getting Started
Do not try to solve all five grids at once. Start with whichever grid has the most givens. Solve as much of it as you can using standard techniques. When you get stuck, move to an adjacent grid. The shared boxes often provide the information you need to make progress in a neighboring grid.
The Shared Box Strategy
The shared 3x3 boxes are your bridge between grids. Every digit you place in a shared box eliminates candidates in both grids. Focus on these boxes when you are stuck. They are usually the most constrained cells in the puzzle and the most likely to yield new placements.
Time Commitment
A Samurai Sudoku takes about three to five times longer than a single 9x9 puzzle. Easy Samurai puzzles might take 30 to 45 minutes. Hard ones can take two hours or more. They are great for weekends or long flights when you want a puzzle that lasts.
Where to Find Them
Samurai Sudoku puzzles appear in specialty puzzle books and on dedicated puzzle websites. They are less common than standard Sudoku but have a loyal following among people who enjoy large, complex logic puzzles.