Rules:
Sudoku: Fill the grid with digits 1–9 so that each digit appears exactly once in every row and column.
Regions: Divide the grid into regions of orthogonally connected cells such that every cell belongs to a region. Each region contains exactly one circle. The digit in a circle gives the size of its region. Digits may not repeat within a region EXCEPT for in regions with a star where at least one digit MUST repeat. Cells separated by a blue dot are in different regions.
Loop: Draw a one-cell-wide loop of orthogonally connected cells which passes through all circles in the grid. The loop may not touch itself, not even diagonally. The loop acts as a German Whispers line (i.e., adjacent digits on the loop must have a difference of at least 5).
A white dot between two cells indicates the digits in those cells are consecutive.
View my other puzzles in this series:
Any feedback is welcomed!
Solution code: Digits in odd-sized regions in row 5 from left to right.
on 13. March 2026, 17:19 by Snookerfan
Brilliant puzzle! I can't believe I missed this one from one of my favourite series. This felt like 3 successive puzzles, which almost could be done without overlap. Thanks and I will try the next one soon.
on 13. March 2026, 01:25 by Silverstep
The bit of math at the start is really good.
on 26. February 2026, 00:46 by Schatzmeister
I am almost tempted to give this puzzle 4 stars only, but probably I just had a run, and it was only easy relative to the monstrous previous iterations.
This one flowed really nicely for me, except the finish which was surprisingly difficult. It didn't help that I made an error halfway through which I only spotted when trying to fill in the last ~15 cells. Luckily, it was a quick fix.
Very nice logic throughout, as usual.
on 5. February 2026, 22:27 by gfoot
Another excellent puzzle, very elegant
on 2. February 2026, 15:06 by Guvenistan
Another brutally hard yet insanely fun puzzle. Forcing us to use 2nd order logic was really nice and rewarding.
on 1. February 2026, 15:33 by Fool on Hill
Very enjoyable puzzle. Threading the needle took some care - rules worked together in some unexpected ways. Every step fair and clean once seen ...