Hard — XY-Wing

Hard Sudoku #39

A hand-graded hard puzzle — 31 clues, roughly 7 minutes. Every puzzle here has exactly one solution, reachable by logic alone.

Hard
00:00

Solved. Nicely done — want another?

What this puzzle needs

Solving this one by logic calls on 5 techniques, from the everyday to the demanding. Each links to a full guide:

One thing to look for

The turning point is an XY-Wing — Pivot r4c2 {4, 5} with pincers r1c2 and r5c1 forces 7 out of every cell that sees both pincers.

Stuck? Let it teach you

Tap Hint once and the solver names the next logical move and the region it lives in — "hidden single in box 4", say. Tap it again to make the move. Nothing here ever needs a guess. Prefer to see the whole solution? Drop this grid into the step-by-step solver.

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