Swordfish
A value's candidate cells across three rows (or columns) line up in the same three columns (or rows) — eliminate it everywhere else in those columns or rows.
How it works
- 1Across rows 1, 3 and 5, every remaining candidate for digit 5 lies in columns 1, 3 or 5.
- 2Those three rows each need a 5, so together they occupy all three cover columns — this is the three-line extension of X-Wing.
- 3Remove 5 from those columns in every other row. The three candidates shown in row 2 are all outside the pattern rows and can be struck.
- Candidates this technique rules out
- Cells read together — The connecting line shows which cells combine to make the deduction.
- Conclusion — The coloured candidate, or the final arrow when it lands outside the pattern, shows the result.