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HONGENJY

RULES & PRACTICE

How to Play Diagonal Sudoku

Play Diagonal Sudoku ↗

Game guide · HONGENJY

The essentials of playing Diagonal Sudoku

Choose a round of Diagonal Sudoku and settle into its rules. 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.

Something to practise

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

The purpose of your moves

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. An attractive position is not enough unless the goal is met. Keep the controls in easy reach.

How a round unfolds

  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.

Your inputs

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 careful first action helps you become familiar with the layout. Look at the feedback after the action.

Learn from a sample situation

On one puzzle in this collection, row 1, column 1 has 3 in its solution. Read the clues on your current board before using that value; another puzzle can need a different entry. Your next round may have a different position, so inspect it before acting. Notice the change in the playing area.

Avoid this misunderstanding

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. When a decision goes wrong, compare it with the common mistake described below. Start again only when you intend to leave the current round.

Game-specific help

While learning, 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?

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.

For a quick reminder, what example helps explain Diagonal Sudoku?

The key detail is this: On one puzzle in this collection, row 1, column 3 has 1 in its solution. Read the clues on your current board before using that value; another puzzle can need a different entry.

While learning, what should I watch out for in Diagonal Sudoku?

For clarity: 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?

The key detail is this: 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?

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.

Before I begin, where should I start with Diagonal Sudoku?

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

For this browser game, 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.

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.

While learning, how do I report an issue with Diagonal Sudoku?

The key detail is this: 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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