Game guide · SHOUJIKON
How to play Diagonal Sudoku
Open Diagonal Sudoku, check the instructions and begin a round. 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 example below to understand a decision. Identify the playing area and the controls you need. Use the example below to understand a decision.
Try a more deliberate round
Before your first action, say what you are trying to achieve. Then compare the result with the goal. Refer to the controls when needed.
What the game asks you to do
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. Notice how the game responds to your input.
The steps to play
- 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.
Choosing and moving on screen
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. Keep the playing area visible while using these controls. Use the visible help when you are unsure of the next input.
See how the rules apply
On one puzzle in this collection, row 1, column 3 has 3 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. Keep the game’s format in mind.
A common point of confusion
Notes are reminders, not final entries. A full board only counts as complete when it satisfies every rule. Check the rule before repeating the action. After a move, check what changed. Decide which rule explains the new state before acting again.
Questions about this game
When I return, what is the goal of Diagonal Sudoku?
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.
While learning, how do I control Diagonal Sudoku?
For clarity: 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.
While learning, what example helps explain Diagonal Sudoku?
On one puzzle in this collection, row 1, column 2 has 2 in its solution. Read the clues on your current board before using that value; another puzzle can need a different entry.
On this playing page, 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.
On this playing page, what format does Diagonal Sudoku offer?
Here is the relevant explanation: Play using the solo mode shown on this page. Read the controls before starting a new round.
On this playing page, which play mode does Diagonal Sudoku use?
For clarity: The mode on this page is Solo. Same-device play uses one screen; this game library does not provide internet matchmaking.
While reading the Guide, where should I start with Diagonal Sudoku?
Here is the relevant explanation: Select an empty cell. The original clues cannot be edited.
On this playing page, do I need an account or a payment for Diagonal Sudoku?
No player account or payment is needed. Game scores are recreational results, not cash prizes.
For my first round, how can I find Diagonal Sudoku again?
The key detail is this: Use the Games list or save this game page in your browser bookmarks. The Guide is linked from the playing page.
Before I begin, how do I report an issue with Diagonal Sudoku?
Use the contact form and include the game name, browser, device and the actions that led to the issue. Do not send passwords or payment details.