Mental Royale
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WXYZ-Wing

Fish & Wings17 / 32

A pivot and three wings juggle four digits — one must give.

The wing family stretched to four cells: a pivot that sees three wing cells, with exactly four candidates shared between the whole quartet. It's a naked quadruple bent around a corner — the four cells don't all share a unit.

One digit Z plays a special role: every other digit is confined to pattern cells that see each other. Without a Z in the pattern, four cells would have to share three digits — impossible. So Z lives somewhere in its pattern cells.

See it in action

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Step 1 of 4

The setup

Start from cells with two to four candidates and collect three peers whose candidates pool with the pivot's into exactly four digits. Then find the digit whose pattern cells don't all see each other — that's your Z. Step through this real position to see it happen.

Practice

Find the WXYZ-Wing and remove its restricted digit from cells seeing all of that digit's pattern cells.

Drill 1 of 29

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