Sudoku is a logic puzzle played on a 9×9 grid. Fill every row, every column, and every 3×3 box with the digits 1 through 9 — each digit exactly once per row, column, and box.

Tap a cell to select it, then pick a digit from the keypad or press a number key on your keyboard. Use pencil marks to jot down candidates you aren't sure of yet. Undo freely — nothing is final until the grid is complete.

You have three lives per puzzle. A wrong placement costs one life. Run out and you can watch a short video to continue, or start a brand-new puzzle from the Start Over option.

Master puzzles strip the grid back to around two dozen given cells — every placement matters. Expect to lean hard on pencil marks and return to the same cell several times before something breaks open.

This is the tier where a single wrong assumption early on can cost you a full restart. Take it slow, verify each placement against row, column, and box, and don't rush to fill in a digit you aren't sure of.