Wednesday, 19 August 2026

4 puzzles · every one solvable by logic alone

Shuzzles · ShudokuWednesday, 19 August 2026

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

25 clues · difficulty rating 430 · 56 logical stepsTechniques: BUG+1Pinch points: 2 (moments with only one move available) · average choices per step 6.5

shuzzles.co.uk/shudoku/2026-08-19/diabolical/

Why this is a Diabolical

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

Rating: 430
Clues: 25
Logical steps: 56
Pinch points: 2one move only
Avg. choices: 6.5per step
Hardest step: BUG+1

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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Lays out as a proper A4 sheet — grid, difficulty and grading. Your print dialog can save it as a PDF.

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

It prints what is on the grid now, pencil marks and all — so you can take a half-finished puzzle with you. Reveal the solution first if you want the answer on paper.

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