Game guide · TIANNBO
Diagonal Sudoku: how a round works
Try Diagonal Sudoku at your own pace and keep its objective in view. 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. Check the relevant rule before repeating a move. Identify the playing area and the controls you need. Choose a clear next step rather than rushing through the instructions.
Take a closer look while playing
After a move, check what changed. Decide which rule explains the new state before acting again. Notice the feedback after each input.
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. Keep that objective in view throughout the round. Keep the controls in easy reach.
The order of 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.
Making selections and moves
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. Read a button’s label before selecting it. Return to the rules if the result is unexpected.
Put the rules into context
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. Apply the same reasoning to the position in your own round. Check the stated objective.
Where a round can go wrong
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. Take enough time to read a new position. If a game has a timer, learn its controls first rather than searching for them during the round.
Answers about the rules and controls
On this playing page, 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.
How do I control Diagonal Sudoku?
Here is the relevant explanation: 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.
On this playing page, what example helps explain Diagonal Sudoku?
Keep this in mind: On one puzzle in this collection, row 1, column 5 has 3 in its solution. Read the clues on your current board before using that value; another puzzle can need a different entry.
What should I watch out for in Diagonal Sudoku?
The key detail is this: Notes are reminders, not final entries. A full board only counts as complete when it satisfies every rule.
For my first round, 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.
While learning, which play mode does Diagonal Sudoku use?
Here is the relevant explanation: The mode on this page is Solo. Same-device play uses one screen; this game library does not provide internet matchmaking.
Where should I start with Diagonal Sudoku?
Keep this in mind: Select an empty cell. The original clues cannot be edited.
Before I begin, do I need an account or a payment for Diagonal Sudoku?
Here is the relevant explanation: No player account or payment is needed. Game scores are recreational results, not cash prizes.
When I return, how can I find Diagonal Sudoku again?
Use the Games list or save this game page in your browser bookmarks. The Guide is linked from the playing page.
As a new player, how do I report an issue with Diagonal Sudoku?
Here is the relevant explanation: 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.
