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SXSS56

RULES & PRACTICE

How to Play Diagonal Sudoku

Play Diagonal Sudoku ↗

Game guide · SXSS56

Getting started with Diagonal Sudoku

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. Look at what changes after your first action. Identify the playing area and the controls you need. Use the example below to understand a decision.

Bring this focus to a round

Locate the buttons and input area before beginning a long round. Use the on-screen labels to avoid an accidental restart. Refer to the controls when needed.

The goal to keep 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. Use the instructions to see which actions move you towards it. Return to the instructions when a step is unclear.

The steps to play

  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. Use the control method described here for this activity. A new-round button replaces the current round.

Learn from a sample situation

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. Compare this with the rule that governs the move. Check the stated objective.

Check this before moving on

Notes are reminders, not final entries. A full board only counts as complete when it satisfies every rule. Read the feedback to see why an action did not have the expected result. Watch the feedback after an action. A message can explain whether the input was accepted or whether a rule needs attention.

Further help with the game

As a new player, 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.

Before I begin, 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.

What example helps explain Diagonal Sudoku?

For clarity: Before filling a cell, compare the symbols already used in its row, column and 3 × 3 region. A candidate must be absent from all three. The two long diagonals must also contain each symbol once.

For a quick reminder, 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.

Before I begin, 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.

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.

On this playing page, where should I start with Diagonal Sudoku?

For clarity: Select an empty cell. The original clues cannot be edited.

While learning, do I need an account or a payment for Diagonal Sudoku?

For clarity: No player account or payment is needed. Game scores are recreational results, not cash prizes.

While learning, 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.

When I return, 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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