THE PLAYBOOK · XHYWQHY
Diagonal Sudoku: instructions and practice
Open Diagonal Sudoku, check the instructions and begin a round. 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. Use the opening round to become familiar with the layout. Keep the game area visible while you use its controls.
Try a more deliberate round
Before your first action, say what you are trying to achieve. Then compare the result with the goal. Make the next step deliberately.
Your goal
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. Check the rules when you are unsure.
Work through the instructions
- 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.
Choosing and moving on screen
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. Make sure you are interacting with the game rather than the surrounding page.
A useful example
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. Use the example as a guide rather than a substitute for reading your board. Read the matching step again.
Notice this detail
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. When a decision goes wrong, compare it with the common mistake described below. Start again only when you intend to leave the current round.
Questions about this game
While reading the Guide, what is the goal of Diagonal Sudoku?
For clarity: 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.
On this playing page, 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.
While learning, what example helps explain Diagonal Sudoku?
The key detail is this: 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.
For this browser game, 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?
Play using the solo mode shown on this page. Read the controls before starting a new round.
For my first round, 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.