Reciprocals
(Published on 23. September 2025, 08:00 by Kaktuslav)
This is a Fog of War puzzle. You can play it on SudokuPad: https://sudokupad.app/gf8l5f4s64
Yin–Yang: Shade some cells in the grid so that all shaded cells are orthogonally connected, all unshaded cells are orthogonally connected, and no 2×2 region is entirely shaded or entirely unshaded.
Reciprocals: Every shaded cell containing digit x has value 1/x; every unshaded cell has value equal to its digit.
Product/Sum cages: Each cage has a corner mark in the leftmost cell of its top row identifying its type. If it shows Σ=X, the values in the cage sum to X; if it shows Π=X, the values in the cage multiply to X (X is not necessarily an integer). Digits or values MAY repeat within a cage.
Dynamic Fog of War: The grid is partially covered in fog. Placing correct digits reveals their own cell and may also lift fog elsewhere in the grid. No guessing is required.
Solution code: Row 3 (with the symbol "/" marking borders between shaded and unshaded cells, e.g. 123/4567/89)
Comments
on 11. July 2026, 22:30 by psams
Really nice from start to end the way each piece clicks into place after careful thought.
on 10. July 2026, 23:53 by sockerbecca
The fractions were the easy parts for me, I am lousy at yin yang.
The puzzle is amazing, I couldn't believe there even was a break-in until I found it :)
on 9. July 2026, 15:42 by wuc
What a math puzzle. The break in is amazing. Without note taking almost 5*. Brilliant puzzle thx.
on 5. July 2026, 13:24 by knight_gx
This was HARD.
on 27. September 2025, 21:22 by Exigus
My brain hurts. But in a good way. Thanks!
on 26. September 2025, 01:25 by zeniko
That‘s some excellent interactions between Yin-Yang and arithmetic. Thanks for sharing.
on 23. September 2025, 14:06 by grrz
Very nice logic!
on 23. September 2025, 14:06 by Playmaker6174
I have to admit that this is your first puzzle that I genuinely had a hard time with, especially that first half [oof].
The logic were very rewarding at different stages, yes, but if one doesn’t grasp the logic at certain points then you likely will be stuck for a while xd
