Game guide · 20ZL
Diagonal Sudoku: how a round works
Read the aim of Diagonal Sudoku, then make your first move. 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
Read one step at a time and try it on the playing area. Match the instruction to the control you use. Make the next step deliberately.
Understand the aim
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. Follow this game’s rules rather than another version’s.
How a round unfolds
- 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.
Getting comfortable with the controls
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. Contact us with the game and device if a control does not respond.
An example to follow
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. Focus on why the action is allowed, not only its outcome. Keep the controls nearby.
Keep this in mind
Notes are reminders, not final entries. A full board only counts as complete when it satisfies every rule. A different version of the game may use a different rule. 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.
Common questions
For a quick reminder, what is the goal of Diagonal Sudoku?
The key detail is this: 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?
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?
The key detail is this: 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.
For this browser game, 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?
For clarity: 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?
Here is the relevant explanation: 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?
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?
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 reading the Guide, 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.