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How to play

1. Fill every row, column and 3 by 3 box with the digits 1 through 9 without repeating a digit.
2. The solver can show a first solution, or keep the given numbers and start a playable version of your custom puzzle.
3. Use the external host's game menu for detailed rules and any restart or save options.

Make your move

• Select a cell and enter 1–9; arrow keys move, Delete clears, P toggles pencil marks, and Ctrl/Cmd+Z undoes.
• Check the host's Help or Controls guide for every key and touch action.
• Denny Games has not verified a complete external game session or device compatibility.

A small head start

• Use pencil marks for candidates and check conflicts before asking for a hint.
• Read the host's controls and rules before starting a longer run.

Compatibility notes

This browser restoration is hosted by the Libre Arcade project on GitHub Pages. Its source repository documents the GPL-3.0 project code plus each game's upstream code and separate asset terms. Denny Games links out only; it does not host the build, game data or artwork. We have not verified a complete external game session or device compatibility.

Denny Games has not verified this external build's gameplay, browser compatibility, controls or save behavior. Check the host's current requirements.

Play style: Number keys. This game runs on an independent host or browser build. Denny Games does not manage its account, session or saves; see the notes above for how this build handles them.

Compatibility

Credits & source

Libre Arcade contributors; original game by Ivonne Engemann and Marcus Wagner · GPL-3.0-or-later browser port · original source LGPL-2.1-or-later. · License detailsSource code · External browser host: Libre Arcade project browser port

Updated: 2026-10-15. Free to play. Pages may contain disclosed affiliate links; Google ads are inactive.