General controls

You can select cells by pressing on them. If you hold down your mouse and drag, you can select several.

You can also press ctrl (or cmd on mac) and press on cells, which will then add them to your selection.

You can also use your mouse arrows to move around the grid.

You can use the following shortcuts:

• z for numbers
• x for cornermarks
• c for centermarks
• v for colors
• b for notes

Numbers (z)

You input a number or a value, by selecting one or more cells and pressing a number from 0-9 or by pressing the numbers on the controller on the right. Press the backspace button to remove the value

Cornermarks (x)

You create cornermarks by selecting a cell and pressing the numbers you want to mark. You can use both the keyboard and the controls on the right. Press the backspace button to remove the cornermarks

Centermarks (c)

You create centermarks by selecting a cell and pressing the numbers you want to mark. You can use both the keyboard and the controls on the right. Press the backspace button to remove the centermarks

Colors (v)

You add colors like you add numbers. The numbers 0-9 match the colors on the right, if you want to use your keyboard instead. Press the backspace button to remove the color

Notes (b)

You can add notes as annotations to any cell to record information that cannot be communicated using the standard pencil mark tools. Cells with with notes will display a marker in the top right corner. Hovering over the marker will show the saved text. Press the backspace button to remove the note

Scanner

The scanning tool can be used to help solve the puzzle by checking whether any cells are restricted to a single digit due to the puzzle rules, or to quickly clean up pencil marks after placing a digit. With Auto-scanning enabled, the scanner will run immediately every time a digit is entered - editing pencil marks will not trigger a scan.

Press (s) to start or stop the scanner.
Press (a) to make a single step.
Press (h) to toggle highlighting on or off.
Press (t) to toggle Tuple highlighting on or off

• Highlighting Mode

  None: No additional cells are highlighted when the selected cells in the grid are changed.
  Seen: Highlight any cells which are seen by the currently selected cell. If multiple cells are selected, only those cells seen by every cell in the selection are highlighted.
  Tuples: Highlight any cells which form a Tuple with the currently selected cell.

  
  

• Scanning Mode

  Basic: The scanner will only use the basic rules of Sudoku when checking available digits.
  Advanced: The scanner can use the puzzle clues when checking available digits.
  Extreme: The scanner can use global negative constraints when checking available digits.

  
  

• Options

  Depending on the scanning mode and the puzzle constraints, you can choose which types of clues can be used by the scanning algorithm.

  
  

• Scanning Speed

  Control how fast the scanner runs.

Walkthrough

The walkthrough is accessed by clicking the icon with the walking person below the controller. When playing a game, you can follow along in the modal, or you can press the button in the top right corner to open the walkthrough in a new tab. If you are creating your own puzzle the same modal can be used to create a walkthrough.

If you don't want to open the modal everytime you want to add a step, you can use the "w" shortcut, which will add the step for you. To add a description you still have to open the modal, though.