Techniques · sudoku and killer sudoku
WXYZ-Wing
Four cells holding four digits between them, where only one digit is not confined. That digit is removed from cells that see all its copies.
In the walkthroughs, every WXYZ-Wing step shades the cells of the pattern and names the cell and digit it proves, so you can see the move on the grid rather than read about it. Press “Skip to next hard step” to jump straight to it.
Worked examples
Puzzles from the books where WXYZ-Wing is used, those where it is the key technique first. Each link opens the full step-by-step solution.
Extreme Sudoku 1 (128 of 150 puzzles)
- Puzzle 42 · Expert 7 · key technique
- Puzzle 96 · Expert 7 · key technique
- Puzzle 1 · Expert 5
- Puzzle 2 · Expert 5
- Puzzle 3 · Expert 5
- Puzzle 4 · Expert 5
- Puzzle 5 · Expert 5
- Puzzle 6 · Expert 5
Extreme Killer Sudoku 1 (2 of 150 puzzles)
Extreme Sudoku 2 (122 of 150 puzzles)
- Puzzle 112 · Expert 7 · key technique
- Puzzle 124 · Expert 7 · key technique
- Puzzle 1 · Expert 5
- Puzzle 2 · Expert 5
- Puzzle 3 · Expert 5
- Puzzle 4 · Expert 5
- Puzzle 5 · Expert 5
- Puzzle 6 · Expert 5
Extreme Sudoku 3 (126 of 150 puzzles)
- Puzzle 64 · Expert 6 · key technique
- Puzzle 1 · Expert 5
- Puzzle 2 · Expert 5
- Puzzle 3 · Expert 5
- Puzzle 4 · Expert 5
- Puzzle 5 · Expert 5
- Puzzle 6 · Expert 5
- Puzzle 7 · Expert 5
Extreme Killer Sudoku 3 (2 of 150 puzzles)
- Puzzle 5 · Expert 2
- Puzzle 107 · Expert 2
Where it sits
See the whole ladder on hard sudoku techniques and hard killer sudoku techniques, or look a puzzle up by number under solutions.
