Normal Sudoku rules apply. Place the digits 1-9 once each in every row, column, and 3x3 box.
The Rainbow:
-Red line: Digits alternate between even and odd parity.
-Orange line: Adjacent digits have a difference of at least four.
-Yellow lines: Digits along the lines read the same backward and forward.
-Green line: Adjacent digits have a difference of at least five.
-Blue line: Box borders divide the line into segments with the same sums.
-Violet line: Contains a consecutive, non-repeating set of digits arranged in any order.
Sandwich: A value outside of the gird gives the sum of the digits that fall between the 1 and the 9 in that value’s column.
Kropki: Cells separated by a white dot contain consecutive digits. Cells separated by a black dot contain digits in a 2:1 ratio. Not all dots are necessarily given.
Mini-rainbows: Within the same row, dominos separated by mini-rainbows either have the same sum or the same difference.
To Play:
SudokuPad