Hard — XY-Wing
Hard Sudoku #15
A hand-graded hard puzzle — 26 clues, roughly 9 minutes. Every puzzle here has exactly one solution, reachable by logic alone.
●Hard
Solved. Nicely done — want another?
What this puzzle needs
Solving this one by logic calls on 6 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 r8c8 {1, 6} with pincers r5c8 and r9c7 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.