Jellyfish
Extreme
Used by Smart Hint
The four-line version of X-Wing and Swordfish — a digit's candidates across four rows fit inside the same four columns.
- Cells that establish the pattern
- Where the conclusion lands
- Candidate ruled out
How it works
- Digit 9's candidates across row 1, row 3, row 5, and row 7 never leave columns A, D, F, and I — the four-row, four-column version of X-Wing and Swordfish.
- That locks 9 into those four columns across those four rows, so it can be eliminated anywhere else in columns A, D, F, or I — including all four cells shown in row 2 (A2, D2, F2, I2).