Antithetical slayer
(Published on 10. February 2026, 05:30 by NicoD)
Rules
Normal sudoku rules apply.
Shade some cells so that all shaded cells are orthogonally connected, and all unshaded cells are orthogonally connected. No 2x2 area may be completely shaded or unshaded.
The value of a shaded cell is equal to the negative of its digit, and the value of an unshaded cell is equal to its digit.
Within a cage, values sum to the small number in the top left corner.
Solution code: Shaded digits in row 5
Comments
on 16. February 2026, 01:47 by virus_dave
Wow, this one was quite tough, but a LOT of fun. Got stuck near the middle for awhile until JUST the right question popped up, then a whole bunch of stuff started to fall into place and it was relatively smooth from there.
Great puzzle, thank you for setting!
on 14. February 2026, 10:43 by Snookerfan
Gorgeous and very tough puzzle! Loved it, thanks
on 11. February 2026, 23:37 by Exigus
That was amazing with lots of interestimg discoveries. Thanks!
on 10. February 2026, 18:22 by Starlight
I found this tough going but really fun. Once I realised the trick to it it went a lot smoother though. Awesome puzzle.
on 10. February 2026, 18:18 by zeniko
There are some very elegant interactions between the two constraints. Thanks for sharing.
