Icewalk Sudoku
(Published on 28. January 2026, 10:08 by KNT)
Place the numbers from 1 to 9 exactly once in every row, column, and box.
Shade some cells in the grid, then draw a loop that passes orthogonally from cell center to cell center through all unshaded cells. The loop may cross itself, but only on shaded cells. The loop must not turn on shaded cells.
If a clued cell is unshaded, the clue indicates the sum of all numbers on the contiguous unshaded segment of the loop that passes through the clued cell.
If a clued cell is shaded, the clue indicates the sum of all numbers in the orthogonally connected group of shaded cells the clued cell belongs to.
For all such groups (shaded and unshaded), numbers must not repeat.
A 1-6 example is provided:
Shade some cells in the grid, then draw a loop that passes orthogonally from cell center to cell center through all unshaded cells. The loop may cross itself, but only on shaded cells. The loop must not turn on shaded cells.
If a clued cell is unshaded, the clue indicates the sum of all numbers on the contiguous unshaded segment of the loop that passes through the clued cell.
If a clued cell is shaded, the clue indicates the sum of all numbers in the orthogonally connected group of shaded cells the clued cell belongs to.
For all such groups (shaded and unshaded), numbers must not repeat.
A 1-6 example is provided:
Solution code: Row 9, then Column 9
Solved by Piatato, han233ing, Myxo, cyddrdrd, henrypijames, r45, elmers, Jesper, misko, Mr_tn, smckinley, BlazingSnow, zuzanina, widjo, LouZX
Comments
Last changed on 28. January 2026, 21:31
on 28. January 2026, 21:31 by cyddrdrd
A cool break in with a wonderful finish!
on 28. January 2026, 21:24 by Myxo
Amazing!
on 28. January 2026, 20:36 by KNT
@henry: Thanks! I haven’t really been gone, I just live more on the nonsudoku pages :-). But this is my first published sudoku with 3x3 boxes since September 2022 (that is, non construction type), so it definitely has been a while!
on 28. January 2026, 20:33 by henrypijames
Wow, welcome back! I'm gonna spend some nice time with this one on my train ride tonight.
on 28. January 2026, 10:13 by Piatato
Great fun, thanks! Nice to see a sudoku from you as well, it brings back good memories from Phistomefel's old hybrids. :-)
