The Big Beach Parity
(Published on 3. October 2025, 14:58 by gdc)
This is a follow up to Sweeping Seas with a simpler ruleset. According to testers (thanks everyone!), the difficulty should be around 1.5-2 stars. If you are new to shading puzzles, see the example below. Hope you enjoy!
Parity Islands: Orthognally connected groups of cells with the same odd/even parity are called "islands".
Circles: A digit in a circle is odd and counts the number of cells in its island.
Squares: A digit in a square is even and counts the number of cells in its island.
Example
Cells were colored for edd/even. Islands are edge-connected groups of the same color. Circles show the size of their orange island. Not all circles/squares are given. Unclued blue islands might have an odd number of cells.
Solution code: The bottom row (row 9) left to right (9 digits).
Comments
on 10. October 2025, 21:12 by bboom
Halfway down the solve it feels like this is never going to be enough information to fill out the whole puzzle, but it all falls into place very neatly.
on 5. October 2025, 12:17 by galium_odoratum
Super fun ruleset!
on 4. October 2025, 15:59 by anothermember
Nice and smooth, a harder 1* or an easier 2*. Now I want to try Sweeping Seas.
on 4. October 2025, 14:08 by IFlaig
Nice puzzle, clean solution :)
on 4. October 2025, 10:37 by Fra314
Beautiful! Smooth as oil and refreshing as water!
on 4. October 2025, 07:57 by Scorps
My first time trying this kind of colouring puzzle. Did OK once I realised an island could contain two clues - got myself in a tangle trying to keep them apart before that brainwave though. Thanks for sharing!
on 4. October 2025, 05:11 by baku
Very fun solving path. Thank you for sharing!
on 3. October 2025, 23:48 by ViKingPrime
The best parity colouring puzzle I've yet seen, which is all the more impressive as it's also likely the most approachable. Excellent setting.
on 3. October 2025, 23:47 by wuc
Great smooth fun 2* puzzle thx.
on 3. October 2025, 22:12 by Exigus
Pretty easy but still very enjoyable. Thanks!
on 3. October 2025, 16:31 by Lorena
“Well, that’s that done” - she thought to herself as she coloured the last of the 81 cells. Then she looked up and saw… a mostly empty grid, with only the squares and circles filled in. She felt a familiar dread inside her, rising unstoppably like the digits on a thermo, as she realised the inescapable truth… sometimes… sometimes… you gotta do sudoku in a sudoku puzzle.
on 3. October 2025, 16:22 by damo_89
I second what Calvinball said
on 3. October 2025, 15:16 by Calvinball
This is a great entry point if you're newer to shading puzzles and a great puzzle if you have more experience with them.
