Mystery Sudoku

Mystery Sudoku takes the classic number puzzle and hides a picture underneath it. Every cell you fill in correctly clears away a little more of the image, so the grid slowly turns from a wall of numbers into a full picture by the time you finish. It still follows all the usual Sudoku rules — each row, column and 3x3 box needs every digit from 1 to 9 exactly once — but now every correct placement feels like it is worth something extra.

The puzzle gives you three mistakes before a level ends, so careless guessing has a real cost. Undo, Erase and pencil-mark Notes are there to help you work through the logic safely, and a Hint is available for the moments you get stuck. Difficulty runs from Easy up through Medium, Hard, Expert, Insane and Genius, with each tier unlocking only after you clear enough levels at the one before it, so the challenge — and the pictures — keep getting better the further you go.