THE PLAYBOOK · SHENGJIQJ
Rules, controls and help for Diagonal Sudoku
Read the aim of Diagonal Sudoku, then make your first move. 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. Look at what changes after your first action. Identify the playing area and the controls you need. Keep the game area visible while you use its controls.
Take a closer look while playing
Locate the buttons and input area before beginning a long round. Use the on-screen labels to avoid an accidental restart. Keep the objective visible.
What you need to achieve
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. Use the instructions to see which actions move you towards it. Take a moment to understand the current position.
A walkthrough of the rules
- 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.
How to use the 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. Use the control method described here for this activity. Make sure you are interacting with the game rather than the surrounding page.
A useful example
On one puzzle in this collection, row 1, column 1 has 2 in its solution. Read the clues on your current board before using that value; another puzzle can need a different entry. Focus on why the action is allowed, not only its outcome. Verify the rule before continuing.
Notice this detail
Notes are reminders, not final entries. A full board only counts as complete when it satisfies every rule. Compare the situation with the worked example. Choose one rule to keep in mind for this round. Apply it consistently rather than guessing what another version might allow.
Read these answers for extra help
When I return, what is the goal of Diagonal Sudoku?
Keep this in mind: 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.
For a quick reminder, how do I control Diagonal Sudoku?
The key detail is this: 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.
When I return, what example helps explain Diagonal Sudoku?
For clarity: On one puzzle in this collection, row 1, column 1 has 5 in its solution. Read the clues on your current board before using that value; another puzzle can need a different entry.
As a new player, what should I watch out for in Diagonal Sudoku?
Here is the relevant explanation: Notes are reminders, not final entries. A full board only counts as complete when it satisfies every rule.
What format does Diagonal Sudoku offer?
For clarity: Play using the solo mode shown on this page. Read the controls before starting a new round.
For this browser game, which play mode does Diagonal Sudoku use?
The key detail is this: The mode on this page is Solo. Same-device play uses one screen; this game library does not provide internet matchmaking.