Sudoku by Nikoli (Nintendo 3DS)
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Get all Sudokus
At the beginning you only have 10 Sudokus but you can unlock more Sudokus until 50 completing the different sudokus.
Sudokus
How to unlock
Sudokus 11 to 20
Solve 5 of 10 sudokus.
Sudokus 21 to 30
Solve 10 of 20 sudokus.
Sudokus 31 to 40
Solve 15 of 30 sudokus.
Sudokus 41 to 50
Solve 20 of 40 sudokus.