Fog of War Sudoku Explained in One Short Example
A 3x3 grid starts with every cell hidden except the center. Placing a correct 4 there clears the fog and shows the clues underneath, a white dot and a green whispers line.
Transcript
The rule
Fog of war sudoku hides most of the grid at the start. When you place a correct digit, the fog clears from the cells around it and shows any clues underneath.
The hidden clues are still part of the puzzle. You solve with what you can see, and each correct digit reveals more of what you need for the next step.
Worth memorizing
Only correct digits clear fog.
A wrong digit leaves it in place, which is itself a clue.
Clues under the fog still count.
You just can’t see them yet.
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