Sudoku By Nikoli Sudoku puzzles
Successfully complete the indicated task to unlock the corresponding set of Sudoku puzzles:
- 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.