Palindrome: Numbers on the grey line must give the same sequence in both directions.
Kropki: Numbers next to a white dot must have a difference of one. Numbers next to a black dot must be in a 1:2 ratio. Not all possible dots are given.
Quads: Numbers in circles must appear in the four adjacent cells.
Even: Numbers in cells marked by grey squares must be even.
Solution code: Column 1, Row 9
on 7. August 2021, 14:17 by uvo_mod
Label Online-Solving-Tool ergänzt, außerdem Variantenkombination statt Rätselvariante und Kropki Pairs statt Kropki.
on 22. May 2021, 20:23 by Kafkapharnaum
Hello! I saw you had crafted some puzzles too, so after your effort on mine I felt I definitely owed you a solve!
That was really clever; I did a whole bunch a coloring before I finally figured what was going on, and even then I didn't get it immediately, so it felt harder than 2 stars to me ;-)
on 25. April 2021, 12:01 by MrBeachHut
Nice puzzle! Love the title :-)
on 22. April 2021, 01:53 by Goofy
Really nice puzzle. I liked the interaction between the Palindrome and the Kropki dots.
on 21. April 2021, 19:37 by Big Tiger
Arrgh, I overlooked one stupid little basic sudoku that left me stumped for 10 minutes! Everything else had a nice logic to it.