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HNSZDS

Solo · FREE PLAY

Diagonal Sudoku

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Sudoku
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Game guide · HNSZDS

The Diagonal Sudoku playbook

Bring your attention to one round 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. Choose a clear next step rather than rushing through the instructions. Identify the playing area and the controls you need. Keep the game area visible while you use its controls.

Bring this focus to a round

Compare the worked example with your own position. Use the reasoning, not an answer copied from a different board. Keep the objective visible.

Aim for this result

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. Start with a deliberate move.

Start here and follow along

  1. Select an empty cell. The original clues cannot be edited.
  2. Choose a symbol from the number pad, or type it on a keyboard.
  3. Turn Notes on to record candidate symbols without committing an answer.
  4. Use Check entries to check your filled values. Hint reveals one value from the verified solution.
  5. Complete the board, or choose New puzzle for another board.

How to interact with the game

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 a smaller screen, keep the active part of the board within view. A new-round button replaces the current round.

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. Compare this with the rule that governs the move. Look for the relevant detail.

Notice this detail

Notes are reminders, not final entries. A full board only counts as complete when it satisfies every rule. Take a moment to reassess the position before continuing. After a move, check what changed. Decide which rule explains the new state before acting again.

Helpful answers for players

While learning, what is the goal of Diagonal Sudoku?

Here is the relevant explanation: 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 reading the Guide, 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.

As a new player, what example helps explain Diagonal Sudoku?

The key detail is this: On one puzzle in this collection, row 1, column 1 has 1 in its solution. Read the clues on your current board before using that value; another puzzle can need a different entry.

For this browser game, 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.

For this browser game, what format does Diagonal Sudoku offer?

Play using the solo mode shown on this page. Read the controls before starting a new round.

When I return, 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.

While learning, where should I start with Diagonal Sudoku?

Keep this in mind: Select an empty cell. The original clues cannot be edited.

While reading the Guide, do I need an account or a payment for Diagonal Sudoku?

The key detail is this: No player account or payment is needed. Game scores are recreational results, not cash prizes.

For this browser game, how can I find Diagonal Sudoku again?

For clarity: Use the Games list or save this game page in your browser bookmarks. The Guide is linked from the playing page.

For this browser game, how do I report an issue with Diagonal Sudoku?

For clarity: 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.

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