THE PLAYBOOK · LOCTITECN
The Diagonal Sudoku playbook
Bring your attention to one round 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. Use the example below to understand a decision. Begin with the solo mode shown on the page. Use the example below to understand a decision.
One thing to notice as you play
When a decision goes wrong, compare it with the common mistake described below. Start again only when you intend to leave the current round. Notice the feedback after each input.
Aim for this result
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. Return to the instructions when a step is unclear.
The order of play
- 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.
Keyboard and screen 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. Keep the playing area visible while using these controls. Use the visible help when you are unsure of the next input.
See the idea in action
On one puzzle in this collection, row 1, column 5 has 3 in its solution. Read the clues on your current board before using that value; another puzzle can need a different entry. Your next round may have a different position, so inspect it before acting. Check the stated objective.
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. Read one step at a time and try it on the playing area. Match the instruction to the control you use.
Read these answers for extra help
On this playing page, what is the goal of Diagonal Sudoku?
Here is the relevant explanation: 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.
While learning, 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?
Here is the relevant explanation: 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.
As a new player, what should I watch out for in Diagonal Sudoku?
The key detail is this: 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?
Play using the solo mode shown on this page. Read the controls before starting a new round.
Before I begin, 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.
