High Low 4

Normal sudoku rules apply. Place the digits 1-9 in each row, column, and box.

High – Low Lines: Digits on each individual line either are only high digits {5-9} or low digits {1-5}. The 5 can be on either line.

Skyscraper: Digits outside the grid indicate the number of digits “seen” from that vantage point with the higher numbers blocking lower numbers.

Kropki Dots: Digits separated by a white dot have a difference of one, digits separated by a black dot have a ratio of 2:1.