Fill in the grid so that every row and every column contains the digits 1 through 8. Each box contains two numbers.

Fill in the triangles around each circle the digits 1 to 6 so that each digit is only used once per circle.

Fill in the triangles around each circle the digits 1 to 6 so that each digit is only used once per circle.

Fill in the grid so that every row, every column, and every outlined region contains the digits 1 through 9.

Fill in the grid so that every row, every column, and every outlined region contains the digits 1 through 9.

Fill in the grid so that every row, every column, and every marked region contains the digits 1 through 9. The grid is joined at the outermost columns as if it were a cylindrical grid.

Fill in the grid so that every row, every column, and every marked region contains the digits 1 through 9. The grid is joined at the outermost columns as if it were a cylindrical grid.

Fill in the grid so that every row, every column, and every marked region contains the digits 1 through 9. The grid is joined at the outermost columns and rows as if it were a toroidal grid.

Fill in the grid so that every row, every column, and cells with the same color contain the digits 1 through 9. (There aren't any boxes.)

Fill in the grid so that every row, every column, and cells with the same color contain the digits 1 through 9. (There aren't any boxes.)