Guides / hard

Level 20 guide: Australia (hard)

A big country with an even bigger reef. A 9×9 board. Colors are named in the steps below, and rows and columns are counted from the top left starting at 1. This guide spoils the solution, so try the level first.

Play level 20

The board

Step by step

12 deductions lead to the 9 stamps. Each placed stamp also rules out its row, column, touching cells and the rest of its region.

1. The stone region has only one cell left: row 9, column 1. Place the stamp there.
2. The amber region can only hold its stamp in column 2, so every other cell in column 2 cannot hold a stamp (5 cells ruled out).
3. The periwinkle region has only one cell left: row 5, column 3. Place the stamp there.
4. The teal region can only hold its stamp in column 9, so every other cell in column 9 cannot hold a stamp (3 cells ruled out).
5. The rose region and the amber region must all put their stamps in rows 1 and 2, so every other cell in rows 1 and 2 cannot hold a stamp (6 cells ruled out).
6. The green region has only one cell left: row 3, column 6. Place the stamp there.
7. The teal region has only one cell left: row 4, column 9. Place the stamp there.
8. The mint region has only one cell left: row 8, column 4. Place the stamp there.
9. The peach region has only one cell left: row 7, column 8. Place the stamp there.
10. The pink region has only one cell left: row 6, column 5. Place the stamp there.
11. The rose region has only one cell left: row 1, column 7. Place the stamp there.
12. The amber region has only one cell left: row 2, column 2. Place the stamp there.

Final solution