Logic Masters Deutschland e.V.

Inside and outside clues, order and chaos, yin and yang... 'Duality' is a follow-up to my previous 6x6-pack Trinity.

I think I was able to put something interesting in each of the puzzles, and I hope you enjoy this collection. The 1st puzzle is the easiest, the 6th is the hardest and you need the right approach to solve it. Puzzles 2-5 should be somewhere inbetween.

Detailled rules and links to the CTC-App can be found below. Happy solving :-)

Big thanks to lerroyy for testing the whole pack!






1) Hot X-Sums

● Normal 6x6 Sudoku rules.
● Numbers along a thermometer increase from the bulb.
● A number outside the grid (which could be a two-digit number) is the sum of the first X cells in the corresponding row/column, where X is the digit in the cell nearest to the clue.


2) Regional Sandwich

● Normal 6x6 Sudoku rules.
● Numbers along a blue line have the same sum N within each region the line passes through. If a line enters a region more than once, each segment of the line sums to N separatley. The outside of the grid is considered a region for the purpose of the sum.
● A number outside the grid (which could be a two-digit number) is the sum of the digits sandwiched between the 1 and the 6 in the corresponding row/column.


3) Chaotic X-Count

● Divide the grid into regions, each consisting of six orthogonally connected cells. Each row, column and region must contain the digits 1-6 once each.
● A questionmark outside the grid indicates that the first X cells in the corresponding row/column are in the same region (and the X+1th cell is in a different region), where X is the digit nearest to the clue.
● The cell with the gray square contains an even digit.


4) Chaotic First Sum

● Divide the grid into regions, each consisting of six orthogonally connected cells. Each row, column and region must contain the digits 1-6 once each.
● A clue outside the grid is the sum of the cells up to the first region border in the corresponding row/column, starting from the cell nearest to the clue.


5) Double The Mines

● Normal 6x6 Sudoku rules.
● The sum of the digits along a gray line is equal to the sum of the digits in the circles at either end of the line.
● Shade some cells such that all shaded cells are orthogonally connected and all unshaded cells are orthogonally connected. No 2x2 area may be fully shaded or fully unshaded.
● The circles act as 'minesweeper' clues. Cells containing a circle are always unshaded, and their value is the number of shaded cells in the surrounding 3x3 area (i.e. the up to eight cells that touch the circle either orthogonally or diagonally).


6) Yin Yang 7-Line

● Normal 6x6 Sudoku rules.
● Colour every cell in the grid in one of two colours such that the cells of each colour are orthogonally connected and no 2x2 is entirely one colour.
● The long line must be devided into non-overlapping segments, each of which sums to 7. Digits may repeat in a segment if allowed by the other rules.
● Additionally, each segment must be entirely one colour, and two neighbouring segments along the line cannot be the same colour.
● Digits along a thermometer increase from the bulb to the tip. Both tips are the same colour *)

*) Small fly in the ointment: One domino is ambiguous in terms of shading so I had to add this extra rule. It does not affect any other logic or the solution, it only resolves the Yin Yang in these two cells.