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Pencil Marks

Pencil MarksSTEP 1/3

Introduction

As the board becomes more difficult, remembering all the options can be challenging. This is where Pencil Marks come in:

They let you enter several small digits into a cell "as a test"
They let you see your alternatives without risking a mistake

These are your notes - the foundation for solving any advanced Sudoku puzzle.

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Pencil MarksSTEP 2/3

How and When to Take Notes

Look at the highlighted cell. Instead of guessing a full digit, the game now activates note-taking mode. A good practice is to:

Enter notes only when there are 2 or at most 3 options in a given area
Write down digits that do not conflict with the current row, column, or box

Notice how the small digits are arranged in the corners of the cell without blocking your view of the whole board.

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Pencil MarksSTEP 3/3

Entering the First Note

Try this solution in practice and see how convenient it is!

Make sure pencil mode (Notes) is enabled in the game panel
Select the highlighted cell and enter some digits as notes

Great! You now have a safe starting point for the elimination process later on.

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