Logic Masters Deutschland e.V.

Colours in the (k)night XIX

(Published on 6. December 2025, 17:26 by Villse)

Next installment in my “Colours in the (k)night” series. I hope you enjoy it :)

Links to the previous parts of the series are given after the rules.

Rules:

Normal Sudoku rules apply. Place the digits 1–9 once in every row, column, and 3×3 box.

Anti-Knight: Cells separated by a knight’s move in chess cannot contain the same digit.

Disjoint groups: Cells in the same relative position in different boxes cannot contain the same digits.

XV: Cells separated by a V sum to 5; cells separated by an X sum to 10. Not all Vs and Xs are necessarily given.

Little killer: Digits along marked diagonals sum to the number indicated outside the grid.

Solve online:Sudokupad

Happy solving!

Here are the links to the previous parts of the series:

Colours in the (k)night

Colours in the (k)night II

Colours in the (k)night III

Colours in the (k)night IV

Colours in the (k)night V

Colours in the (k)night VI

Colours in the (k)night VII

Colours in the (k)night VIII

Colours in the (k)night IX

Colours in the (k)night X

Colours in the (k)night XI

Colours in the (k)night XII

Colours in the (k)night XIII

Colours in the (k)night XIV

Colours in the (k)night XV

Colours in the (k)night XVI

Colours in the (k)night XVII

Colours in the (k)night XVIII

Solution code: Row 1 (9 digits)

Last changed on -

Solved by jordanza, keenbowl, weiken, Marshal on Mars, tuturitu, jalebc, Dentones, SKORP17, apendleton, Bjd, gxorgx, SincereEngineer, Elliott810, Azumagao, BenClancy, Rex, by81996672, ankpress, Blake Saligia, ... CorpJigsQuand, mse326, TaeChi, Asphodel, dtoto, SFP, Corey115, Not_a_contraction, BellBear, pms_headache, actboy168, Jdt112, nighthawkranger, bcreturnee, Gullie, BeckLynn14, tiredsudoku, wotmania505
Full list

Comments

on 9. December 2025, 01:31 by Exigus
That was amazing. But I probability missed a trick or two, took me quite some time. Loved it though. Thanks!

on 9. December 2025, 00:26 by itsid
That was great..
I couldn't see what alex saw at all... (I had perfectly fine options against his claim for very--VERY-- long!)
IDK I'm sure there was a cleverer way of doing it, but in the end I jumped off the cliff and made a bold decision and then backtracked to that mistake, since I couldn't find the contradiction other than by bifurcating sadly.
Once that was out of the way however, it suddenly fell apart entirely and essentially solved itself

Anyways, it's been a great puzzle, too bad I'm not sure I'm fit for that kind of difficulty ;-)

on 8. December 2025, 15:03 by Frankster
Another excellent instalment in the series!

on 6. December 2025, 21:13 by alexsmart
With these minimalist disambiguating clues, it is so tempting to try and use them earlier than intended. Like with this puzzle, looking at the 14 clue, I could immediately tell that the only way this puzzle disambiguates is if the 14 diagonal had two big digits on it.

I wonder if it is ever a valid technique to use in the spirit of the "uniqueness" techniques in normal sudoku.

Difficulty:4
Rating:96 %
Solved:63 times
Observed:2 times
ID:000PL3

Puzzle variant Variant combination New

Enter solution

Solution code:

Login