THE PLAYBOOK · SLTPPF
How to play Diagonal Sudoku
A round of Diagonal Sudoku at SLTPPF begins with understanding the objective. Fill all cells with 1–9; do not repeat a symbol in any row, column or region. The two long diagonals must also contain each symbol once. The learning focus here is review the result, supported by the rule notes below.
Review the result
When a round finishes, compare what happened with the winning or scoring condition. Use that comparison to choose a better approach next time.
Your goal
Fill all cells with 1–9; do not repeat a symbol in any row, column or region. The two long diagonals must also contain each symbol once.
Step by step
- Select an empty cell. The original clues cannot be edited.
- Choose a symbol from the number pad, or type it on a keyboard.
- Turn Notes on to record candidate symbols without committing an answer.
- Use Check entries to check your filled values. Hint reveals one value from the verified solution.
- Complete the board, or choose New puzzle for another board.
Controls
Tap or click a cell and use the number pad. Keyboard: arrows select cells; digits (and A–G on 16×16) enter values; Backspace erases.
A useful example
Before filling a cell, compare the symbols already used in its row, column and 3 × 3 region. A candidate must be absent from all three. The two long diagonals must also contain each symbol once.
Watch out for this
Notes are reminders, not final entries. A full board only counts as complete when it satisfies every rule.
Common questions
How does this round end?
Fill all cells with 1–9; do not repeat a symbol in any row, column or region. The two long diagonals must also contain each symbol once.
Can I play without an account?
Yes. This game runs in your browser without an account or a payment. There are no cash prizes.
How do I start over?
Use the New round, New puzzle or Start again control above the playing area. Starting again clears the current round.
