Mental Royale
All techniques

Finned X-Wing

Fish & Wings19 / 32

An X-Wing with a blemish — the fin limits the damage.

Almost an X-Wing: one of the two rows carries one or two extra candidates — the fin — sitting in a single box. The clean eliminations don't all survive, but some do.

Split into cases: if the fin is false, the clean X-Wing works. If the fin is true, it claims its box. Cells caught by both cases — X-Wing eliminations inside the fin's box — are gone either way.

See it in action

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Step 1 of 4

The setup

When an X-Wing almost works but one row has a stray candidate or two, check whether the strays share a box with one of that row's pattern columns. Step through this real position to see it happen.

Practice

Find the finned X-Wing and remove its digit from the covered cells inside the fin's box.

Drill 1 of 29

Tap a cell, then the candidate digit you want to remove.