Fill in the grid so that every row and every column contains the digits 1 through 8 exactly once. In each cell the upper left triangle contains a digit that is less then the digit in the lower right part of the same cell.

Fill each 4x4 grid with the digits 1 to 4 so that each row and column of each 4x4 grid has each digit. Neighboring squares from separate grids do not have the same number.

Fill the grid with the digits 1 to 6. The digits represent the height of the skyscraper in each cell. Each row and column has exactly one of each digit. The clues along the edges tell you how many skyscrapers you can see from that vantage point. The sum of the cells in the marked cages is always the same.

Fill the grid with the digits 1 to 6. The digits represent the height of the skyscraper in each cell. Each row and column has exactly one of each digit. There are no neighbouring houses with consecutive skyscraper heights. The clues along the edges tell you how many Skyscrapers you can see from that vantage point.

Fill the grid with the digits 1 to 9. Each row and each column has exactly one of each digit. Each red region must contain 1 pair of numbers. Each cyan region must contain 2 pairs of numbers. Each yellow region must contain 3 pairs of numbers.

Fill in the grid so that every row, every column and both diagonals contain the digits 1 through 9. Each blue line marks that the sum of the two neighbored cells is 11.

Fill in the grid so that every row and every column contains the digits 1 through 6. The 7's are the sum of the digits in adjazent cells.

Fill in the grid so that every row, every column contains the digits 1 through 8. On the same brick never should be two odd or two even numbers.

Fill in the grid so that every row, every column contains the digits 1 through 8. On the same brick never should be two odd or two even numbers.

Fill in the grid so that every row, every column contains the digits 1 through 6. On the same brick never should be two odd or two even numbers.