Logic Masters Deutschland e.V.

When I had the idea for this ruleset, it seemed really cool. I maintain that it has potential, but the setting process that followed was brutal. The resulting puzzle is very difficult, and while some deductions I think are quite interesting and satisfying, many others verge on trial and error (though I'd argue that, when asking the right questions, none of the bifurcation chains are unfairly long). Therefore, I feel I ought to acknowledge that this puzzle will only appeal to a certain type of solver, so I won't be offended by anyone who chooses to pass on this one - I simply had to publish it to justify the sheer amount of time I spent agonising over it!

I have made two versions, one for the keypad as SudokuPad displays it, and one as most computer keyboards display it - see the links below. The puzzles are essentially identical, so feel free to choose your preference. Due to the perfectly symmetrical nature of the clues, one could even play it with a (321/654/987) or (987/654/321) keypad, though solution checking won't work for either of these!



Play the (123/456/789) keypad version
Play the (789/456/123) keypad version

Normal sudoku rules apply.

Compass Lines: Small numbers show the sum of all digits on the "Compass Line" beginning in that cell. A Compass Line is drawn by moving from a cell in the direction indicated by that cell's digit's position on the keypad.

The line ends either at a 5 (the 5 counts towards the line's total), or when its next move would make it revisit a cell. Clued Compass Lines may not leave the grid (a hypothetical Compass Line beginning on e.g. the 7 in column 1 would leave the grid, but this line is not clued).