- 26 - straight sudoku.png (34.05 KiB) Viewed 4059 times
Potential issue: lack of regions. Here we have only one "full" regions, and a few other renban groups, which can be described as deficit regions. The major part of the grid has no third constraint (i don't consider a single cell as a deficit region).
I chosed the competition puzzle because the example in the instructions booklet was more acceptable in my opinion, with more cells being part of a renban group.