THE PLAYBOOK · YUBOJIAGU
How to play Diagonal Sudoku
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. Keep the game area visible while you use its controls. Begin with the solo mode shown on the page. Look at what changes after your first action.
Review a difficult moment
When a decision goes wrong, compare it with the common mistake described below. Start again only when you intend to leave the current round. Use the example to check your reasoning.
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. An attractive position is not enough unless the goal is met. Notice how the game responds to your input.
Step by step
- 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.
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. Read a button’s label before selecting it. Return to the rules if the result is unexpected.
A useful example
On one puzzle in this collection, row 1, column 3 has 3 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. Look for the relevant detail.
Watch out for this
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. Watch the feedback after an action. A message can explain whether the input was accepted or whether a rule needs attention.
Common questions
For a quick reminder, 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.
For this browser game, 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.
For this browser game, what example helps explain Diagonal Sudoku?
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 this browser game, 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 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.
For a quick reminder, which play mode does Diagonal Sudoku use?
The mode on this page is Solo. Same-device play uses one screen; this game library does not provide internet matchmaking.
