Rules:
Normal Sudoku rules apply.
In addition, shade some cells such that every orthogonally connected group of shaded cells joins to the edge of the grid, and all unshaded cells form one orthogonally connected area — the “cave”.
A number clue in an unshaded cell tells you the sum of the digits that can be “seen” in the cave from this cell in all horizontal and vertical directions, including the digit in the clued cell itself. Shaded cells block the view. Digits may not repeat within this sum (that is, within the field of vision of an unshaded number clue).
A number clue in a shaded cell tells you the sum of the digits in its orthogonally connected group. Digits may not repeat within any orthogonally connected group of shaded cells, even if it does not contain any number clues.
Example (6x6):
Link for online solving: Penpa+
(Solution check requires all digits to be filled, as well as for all shaded cells to be correctly filled in using light grey, grey, or dark grey.)
Setter's preface:
This puzzle is quite possibly my hardest and most intricate creation so far. It is constructed in a very particular style which may not appeal to all tastes, but I have worked hard to ensure that the puzzle can be solved through logical deduction alone. Good luck!
Lösungscode: Row 5 and column 8 (18 digits in total)
am 1. August 2022, 22:51 Uhr von lerroyy
Really nice puzzle! Incredible that the grid is symmetrical with the clues.
am 1. August 2022, 18:13 Uhr von Jesper
Extremely challenging but also very rewarding, thanks!
am 29. Juli 2022, 01:30 Uhr von Niverio
Absolutely, monstrously brutal.
am 28. Juli 2022, 09:51 Uhr von Phistomefel
So far, I have solved the example puzzle and I have to say, this is top-notch. I'm very much looking forward to solving the actual puzzle, albeit with some trepidation after reading the comments.
am 28. Juli 2022, 03:20 Uhr von RJBlarmo
Extremely difficult puzzle from start to finish, really enjoyed it.
am 28. Juli 2022, 00:58 Uhr von the_cogito
Very cool start. Very hard end.
am 27. Juli 2022, 20:44 Uhr von henrypijames
Another puzzle where I wandered forever in the wilderness before getting any idea of where to even begin.
am 27. Juli 2022, 18:05 Uhr von polar
Tough puzzle with lots of beautiful deductions. Very enjoyable solve - thanks :)
am 27. Juli 2022, 16:22 Uhr von abed hawila
Mindblowing puzzle!
Very hard, but rich in rewarding "Logical" deductions.
Very well constructed, I loved it!
Thanks ;)
am 27. Juli 2022, 12:16 Uhr von Vebby
Very challenging yet very rewarding to solve. Some awesome logic woven into this one. I highly recommend getting acquainted with the ruleset via the example puzzle first.
am 27. Juli 2022, 08:59 Uhr von KNT
It was an absolute honor to be able to test this, hours of fun! It is so, so intricate and rewarding the whole way through. For the sake of your intellectual enrichment, pleasure, or both, please absolutely do not miss this puzzle!