GridWits

Swordfish

Expert Used by Smart Hint

X-Wing's three-line cousin: a digit's candidates across three rows fit inside the same three columns (or vice versa).

A 1 B 2 C 3 D 4 E 5 F 6 G 7 H 8 I 9 3 8 5 8 7 8 1 8 3 8 2 8 6 8 8 9 4 8

How it works

  1. Digit 8's candidates in row 1, row 4, and row 7 all fall inside columns B, E, and H — never more than that, and every row uses at least two of them.
  2. That's a Swordfish: across these three rows, 8 must occupy exactly those three columns. Any 8 elsewhere in columns B, E, or H can be eliminated — including all three cells in row 3 (B3, E3, H3).

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