Logic Masters Deutschland e.V.

Hello.

I've been wanting to make another 'Islands' puzzle for a while, as a follow-up to Modular Islands and Entropic Islands, both of which are rated 2 stars for difficulty.

Working with unknown sets turned out to be a really fun and interesting setting experience. Rather than using our beloved Kropki dots, as I did in the previous two puzzles, I decided to lean much more heavily into the geometry and negative constraint. These are used to force groups and digits into the grid, making this puzzle a little more challenging. However, the logic is always fair.



Normal Sudoku rules apply.

Divide the digits 1-9 into 3 distinct 'mystery sets' of 3 digits each. Which digits belong to each set is to be determined by the solver.

A digit placed in a circle indicates the size of the orthogonally connected group of cells that ALL contain digits from the same mystery set as that digit.

No group contains more than one circled cell.
Not all groups contain a circle.

Digits separated by a red diamond must not have a 2:1 ratio.

Have fun.