Thursday, 20 August 2026

4 puzzles · every one solvable by logic alone

Shuzzles · ShudokuThursday, 20 August 2026

DiabolicalSwordfish, XYZ- and W-Wings, unique rectangles. Still pure logic — but only just.

28 clues · difficulty rating 430 · 60 logical stepsTechniques: Pointing Pair/Triple ×3, Naked Pair, Box/Line Reduction, Y-Wing, XYZ-WingPinch points: 5 (moments with only one move available) · average choices per step 5.4

shuzzles.co.uk/shudoku/2026-08-20/diabolical/

Why this is a Diabolical

Swordfish, XYZ- and W-Wings, unique rectangles. Still pure logic — but only just.

Rating: 430
Clues: 28
Logical steps: 60
Pinch points: 5one move only
Avg. choices: 5.4per step
Hardest step: XYZ-Wing

Techniques the solve needs

Every technique, explained →

Difficulty is measured by solving the puzzle the way a person does and watching how hard it pushes back — never by counting blank squares.

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Print this puzzleExactly as you see it All four of today'sOne sheet, plus solutions

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