Caves can hide secrets
(Published on 8. February 2026, 17:45 by cornish-john)
This is a puzzle that I created as part of a Secret Santa gift this year for
Calvinball, and he was kind enough to suggest that I share with all of you as well.
Ratings, comments, and feedback are much appreciated! Please feel free to reach out to me on Discord if you have any comments or questions.
Click on the puzzle image or the link below to play
Rules:
Normal sudoku and arrow rules apply.
Sudoku: Fill the grid with the digits 1-9 with no repeats in rows, columns and boxes.
Arrows: Digits in a circle sum to the value of the digits on the attached arrow.
Cave: Shade some cells in the grid such that they form an orthogonally connected area. All unshaded cells must be part of an orthogonally connected group that contains all the digits 1 to N exactly once, where N is the size of that group. All groups must be connected to the outside of the grid. All circles (including arrow bulbs) are unshaded.
Solve here:
Sudokupad
Break-in hints:
Checkerboarding is not allowed in the shading, therefore diagonally touching unshaded cells must be part of the same group.
Of the bulbs that are in the top half of the puzzle, there are some that now have very limited degrees of freedom.
Solution code: Shaded digits of row 8 from left to right.
Solved by Calvinball, tuturitu, gdc, Fool on Hill, CaballeroOscuro, cryptique, Chaossudokusplease, Agent, Piff, damo_89, dogfarts, trashghost, Paletron, bansalsaab, Graphael, mse326, Isael, pmatos, Bravissimo, ... smckinley, Khatru, AlSina, madhupt, Lithium-Ion, nixxo, SKORP17, Ramez, mew_rocks, thargian, Morisenseiisgod, Dumas, jkuo7, alta1r, garage, y00j1n, QuiltyAsCharged, OGRussHood, BlazingSnow
Comments
yesterday, 08:40 by QuiltyAsCharged
Lovely puzzle. The opening steps are quite challenging. I actually checked the hints after 30 minutes, and they told me to do what I was already doing, lol.
But once you narrow things down, it's really satisfying to see how the cave walls magically snap into place!
on 8. February 2026, 23:21 by Fool on Hill
This was a beautiful gift and is an excellent puzzle.
on 8. February 2026, 21:25 by Calvinball
My final boss of Secret Santa, had a blast with this one.
on 8. February 2026, 21:08 by gdc
Very fun! I rarely solve cave puzzles, but this one clicked very well with me.