Logic Masters Deutschland e.V.

Rules

• Normal quattroquadri rules apply and all clues are standard.
• Place the digits 1-9 once each in every 3x3 box. Digits may not repeat in any box, row, or column.
• Digits along a grey thermometer must strictly increase from the bulb end.
• Digits along an arrow sum to the digit in the attached circle.
• The digit in the fully shaded grey fortress cell must be larger than the orthogonally adjacent non-fortress cells.
• Adjacent digits along a green line must differ by at least 5.
• Adjacent digits along an orange line must differ by at least 4.
• Box borders separate a blue line into segments of equal sum.
• Where a black dot separates two digits, one must be double the other.
• Digits separated by an X sum to 10.
• Digits separated by a V sum to 5.
• A purple line contains a non-repeating consecutive set of digits in any order.
• A digit in a circle must appear in one of the four cells touching that circle.
• A number outside the grid is the sum of all digits that appear on the indicated diagonal.