Game guide · CXCWGS
Diagonal Sudoku: learn through an example
Diagonal Sudoku gives you a focused activity to play in your browser. 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. Keep the game area visible while you use its controls.
Practice beyond the first move
Choose one rule to keep in mind for this round. Apply it consistently rather than guessing what another version might allow. Use the example to check your reasoning.
The challenge in front of you
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. The feedback beside the game helps you follow the round. Notice how the game responds to your input.
How to proceed
- 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.
The controls to know
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. Use the visible help when you are unsure of the next input.
A useful example
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. Use the example as a guide rather than a substitute for reading your board. Keep the controls nearby.
One detail worth checking
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. Before your first action, say what you are trying to achieve. Then compare the result with the goal.
Clarifying the way this game works
For my first round, 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.
As a new player, how do I control Diagonal Sudoku?
Keep this in mind: 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.
When I return, what example helps explain Diagonal Sudoku?
Keep this in mind: On one puzzle in this collection, row 1, column 1 has 5 in its solution. Read the clues on your current board before using that value; another puzzle can need a different entry.
While reading the Guide, what should I watch out for in Diagonal Sudoku?
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?
For clarity: 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?
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.
For a quick reminder, where should I start with Diagonal Sudoku?
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?
Keep this in mind: No player account or payment is needed. Game scores are recreational results, not cash prizes.
For a quick reminder, how can I find Diagonal Sudoku again?
Here is the relevant explanation: Use the Games list or save this game page in your browser bookmarks. The Guide is linked from the playing page.
For a quick reminder, 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.