52 empty cells
Hard
58 empty cells
Expert
45 empty cells
Odd-Even
48 empty cells
Diagonal
45 empty cells
Odd-Even
35 empty cells
Easy
48 empty cells
Diagonal
58 empty cells
Expert
50 empty cells
Killer
45 empty cells
Medium
52 empty cells
Hard
58 empty cells
Expert
35 empty cells
Easy
45 empty cells
Medium
52 empty cells
Hard