Normal Sudoku rules apply.
FOG OF WAR: Not all clues are visible at the start; correct placements will reveal new cells and clues.
PALINDROME (black line): reads the same from both ends.
GERMAN WHISPERS (green lines): adjacent digits differ by at least 5.
RENBAN (pink line): digits form a set of consecutive digits, in any order, without repeats.
THERMOMETERS (grey): digits strictly increase from bulb to tip, without repeats.
KILLER CAGES (dashed): digits sum to the given clue (top-left corner), with no repeats within a cage.
SQUARES = even digits.
CIRCLES = odd digits.
X between two cells = sum 10.
V between two cells = sum 5.
BLACK KROPKI DOT: One cell is double the other.
In the grid there are exactly nine colored regions, made of orthogonally connected composite digits. Each region has a sum that is a prime number (to be determined by the solver).
No Composite Numbers Allowed: White cells may not contain composite digits, so only 1, 2, 3, 5, 7 are possible there.
Consistency of clues: Consistency of clues: Whenever part of a clue (line, cage, thermometer, etc.) is revealed, its background determines the whole clue. If the revealed cell is white, then all cells of that clue are white. If the revealed cell is colored, then all cells of that clue are in the same color.
Play online in SudokuPad.Solution code: Enter the digits in Row 3 from left to right without spaces.
yesterday, 10:59 by SudokuFan
Drawing in the colored regions with gray lines resulted in the gray lines covering up the palindromes, which were the exact same width lol
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I'll keep this in mind for future puzzles. Thank you!
on 26. August 2025, 19:32 by BG03
Two fun puzzles rolled into one. Thanks for sharing!
on 25. August 2025, 18:56 by johnreid
This was great fun, thank you!
on 25. August 2025, 17:01 by ACK
This was great fun, I really enjoyed solving it.
on 25. August 2025, 16:24 by nearestneighbour
Amazing puzzle, I'll keep an eye on you
on 25. August 2025, 15:25 by Snaques
I have to admit that I was pretty worried about the amount of hand holding in the beginning, but in the end it turned out to be a fun puzzle. I bet at least some of your students will enjoy and learn while at it.
on 25. August 2025, 15:09 by pfox
Oh that was wonderful. Refreshingly different ruleset.
on 25. August 2025, 12:28 by Myfyr MJ
Unusual but fun.
on 25. August 2025, 05:06 by NorthCoastAsher
Beautiful and satisfying puzzle once you understand the constraints!
on 25. August 2025, 01:11 by Exigus
Very nice construction. Thanks!
on 24. August 2025, 23:05 by Ragna
Good idea. Thank you. :-)
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