Logic Masters Deutschland e.V.

Every row, column and 3x3 box must have the digits 1-9, without any of the digits repeating in any row, column or 3x3 box.

Digits separated by a white dot must be consecutive. (i.e. if the first digit is 3, the second digit must be 2 or 4).
Digits separated by a black dot must have a ratio of 1:2. (i.e. if the firs digit is 3, the second digit must be 6). Not all dots are given.

Digits separated by an X must sum to 10. Digits separated by a V must sum to 5.

Digits within a cage must sum to the total in the top left corner of the cage.

Digits within a cage must multiply to the total in the top left corner of the cage. (The only product cage in this puzzle is highlighted in red)

Neighbouring digits along a German whisper line, must have a difference of at least 5. (i.e. if the first digit is 3, the second digit must be an 8 or 9).

All green cells contain the same digit. All yellow cells contain the same digit. All blue cells contain the same digit. Colours are not mutually exclusive (i.e. blue and yellow cells could all contain the same digit, if all other rules allow).

Digits on a light grey square must be even. Digits on a light grey circle must be odd.

Draw a continuous path which connects the 2No. light bulbs. The path may move orthogonally or diagonally 1 cell at a time. The path may not visit any cell more than once. The path may not cross itself. The path must not enter any red coloured cell. The path must visit every blue, green and yellow cell. The path between the light bulbs operates as a German whisper line. The total value of the product cage (highlighted in red) is equal to double the total sum of all the digits along the path connecting the light bulbs (including the digits on the lightbulbs). (i.e. if the sum of all the digits on the path connecting the bulbs equals 30, then the product of the 4No. digits in the red cage is 60).