Advanced family · 01

Fish

One candidate. Multiple lines. A structural elimination.

The fish family

ONE NUMBER AND ITS RECTANGLE PATTENS.

Fish patterns track one candidate number across multiple lines, i.e., rows and columns. Start with the two-line (two rows and two columns) X-Wing, then extend the same structural idea to three-line (three rows and three columns) Swordfish and four-line (four rows and four columns) Jellyfish. Comparing with other advanced techniques, they are easier to spot, simply foucs on one number and its "rectangle" formed by lines.

The question: What candidate structure in this family is present in the grid?

Explore the family

FISH TECHNIQUES

01 · Fish

X-Wing

A number is restricted to two matching columns across two rows.

X-Wing →

02 · Fish

Swordfish

The same fish logic expands to three base and cover lines.

Swordfish →

03 · Fish

Jellyfish

The fish structure expands again to four lines.

Jellyfish →

MORE FISHES

There are more fishes.

Squirmbag with 5 lines, Whale with 6 lines, and Leviathan with 7 lines. These fishes are more advanced and rarely occurs. With the three fishes you learn here, you will be able solve lots of puzzles.

What about Turbot Fish?