Logic Masters Deutschland e.V.

When I started setting this puzzle, I wanted it to be about making something with good "lying" logic, inspired by the concept developed in other "2 truth and 1 lie" puzzles. Then, it occured to me it was coincidentally going to be my 13th deconstruction puzzle. So, I had this idea to include some funny/trolling elements and make a design that would vaguely resemble a scary joking face... The ruleset is quite long because there are a lot of variant rules included and I needed to describe how they behave in this deconstruction. However, I believe it won't be a problem to digest them if you're familiar with the individual variants. Anyway, I had fun setting this. And I hope it will also "put a smile on that face" of yours while solving !

The puzzle :

Play on Penpa

Play on Sudokupad

Rules :

- Normal sudoku deconstruction apply : Fill the grid with 9 non-overlapping 3x3 square regions, such that each region contains the digits 1-9 once each and no digit repeats in any row or column. Cells outside regions do not contain digits.

- 2 truths 1 lie clues : For each of the following clue types, exactly two of the appearances of that clue are correct, and the other is incorrect. See each clue type description for precisions about the definition of correct/incorrect.

- White Kropki dots : Cells across white dots contain consecutive digits. If the digits are not consecutive or one of the cells is empty, the clue is incorrect.

- Black Kropki dots : Cells across black dots contain digits at a 1:2 ratio. If the digits are not in a 1:2 ratio or one of the cells is empty, the clue is incorrect.

- Diamond with a "?" : Cells across a grey diamond are in a ratio to be determined by the solver. That ratio must be the same for the 3 diamonds.

- X : Cells across an X sum to 10. If the digits don't sum to X or one of the cells is empty, the clue is incorrect.

- Killer cage : the digits in a cage must sum to the total in the top left corner.

- Arrows : Digits along an arrow sum to the digit in that arrow's circle. To be clear, there are 3 arrows sharing the same circle, and the 2 cells in R6C5 and R6C7 belong to the same arrow. There can be empty cells on a valid arrow.

- Region sum line : Blue lines must have an equal sum S within each region they pass through. If a line re-enters a region, each segment sums to S separately. There can be empty cells on a valid region sum line but it must pass through at least 2 regions.

- Ten-line : ignoring empty cells, grey lines can be broken into one or more strings of digits which sum to 10. Digits may repeat freely on a ten-line. (Example : 6-2-empty-2-7-3)

- German Whispers : on a green line, ignoring empty cells, adjacent digits must differ by at least 5. A correct line must have at least 2 digits on it. (Example : 7-empty-2-8)

- Renban : on a purple line, digits must form a set of non repeating consecutive digits in any order. A correct line must have at least 2 digits on it.

- Zipper line : on a red line, ignoring empty cells, the rest of the digits must form a zipper sequence, where digits an equal distance from the centre of the sequence must sum to the digit in the centre of that sequence. A correct line must have at least 3 digits on it. (Example : empty-3-empty-9-6)

- X-sums : clues outside the grid give the sum N of any digits in the first X cells from the direction of the clue, where X is the first digit in that direction. To be clear, N is the same for the 3 clues and its value has to be determined by the solver. (Example : for N=9, it could be, EE456E... where E are empty cells)

- Odd : grey circles contain odd digits.

Example puzzle (with kropki dots and X/V) :

Play on Penpa

Play on Sudokupad