Samurai Sudoku, Explained

Five grids in one

A Samurai Sudoku is made of five nine by nine grids arranged in a cross. There is one in each corner and one in the middle, and the middle grid overlaps a corner box of each of the other four. So the four outer grids share their inner corner regions with the central one. Every individual grid still follows all the normal Sudoku rules.

The overlaps are the whole trick

The cells in an overlapping box belong to two grids at once, which means they must satisfy the rules of both. That double duty is exactly what makes Samurai solvable and enjoyable. A value you place from the central grid instantly gives a clue to a corner grid, and the other way around. The shared boxes are bridges, and information flows across them in both directions.

How to approach it

1. Treat each of the five grids as its own Sudoku and solve the easy placements in each.
2. Pay special attention to the four overlap boxes, since progress there helps two grids at once.
3. When one grid stalls, move to a neighbor. A placement there often unblocks the shared box.
4. Keep cycling between the grids, letting each solved cell ripple across the overlaps.
5. Use candidates in the overlaps carefully, remembering they must fit both grids.

Why people love it

Samurai Sudoku rewards the same skills as a normal puzzle but on a grander scale, with the extra pleasure of watching progress in one corner cascade across the whole cross. It feels like a marathon rather than a sprint, and finishing one is genuinely satisfying. If a single grid has started to feel easy, Samurai is a great way to stretch the same logic further.

Build the skill first

Because it is just five linked Sudoku puzzles, the way to get good at Samurai is to get comfortable with a single grid first. Solid scanning and candidate work on ordinary boards, the kind you can practice in Shapedoku from Easy to Extreme, is exactly what you carry into the bigger puzzle. Master one grid, and five joined together become a pleasure rather than a fright.