Every bold outlined section must contain the consecutive integers from 1 to the quantity of cells in that section inclusive. Adjazent cells must be different, even if they are diagonally adjazent. In rows or columns the digits can be repeated,

Fill the grid with the digits 1 to 9. The digits represent the height of the skyscraper in each cell. Each row, column and 3x3-box has exactly one of each digit. The clues along the edges tell you how many skyscrapers you can see from that vantage point. Taking 180-degree rotational symmetry, the sum of mirrored skyscrapers must be 10.

Fill the grid with the digits 1 to 9. The digits represent the height of the skyscraper in each cell. Each row, column and 3x3-box 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 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 in the grid so that every row, every column, and every 3x3 box contains the digits 1 through 8 and a chess king. Kings can be neither orthogonally nor diagonally adjazent.

Fill in the grid so that every row, every column, and every 3x3 box contains the digits 1 through 8 or a chess piece (1 queen and 8 knights). No chess pieces attack each other.

Fill in the grid so that every row, every column, and every 3x3 box contains the digits 1 through 9. The same numbers are not "chess-knight move connected".

Fill in the grid so that every row, every column, and every 3x3 box contains the digits 1 through 7 and two chess knights. No knights attack each other.

Fill in the grid so that every row, every column, and every 3x3 box contains the digits 1 through 7 and two chess knights. All knights defend at least one other.