Kuromasu by JinHoo Ahn
or solve online (using our beta test of Penpa-Edit tools; use tab to shift between shading mode and the linex mode where left click+drag draws lines and right click marks X’s)
Theme: Double Sequences
Author/Opus: This is the 44th puzzle from our contributing puzzlemaster JinHoo Ahn.
Rules: Shade some empty cells black so that each number indicates the total count of white cells connected vertically and horizontally to that number including the numbered cell itself. Black cells cannot share an edge, and all white cells must belong to a single connected group.
Also see this example:
Difficulty: 1 star
Time Standards (highlight to view): Grandmaster = 0:30, Master = 1:00, Expert = 2:00
Solution: PDF; a solution video is also available here.
Note: Follow this link for more Kuromasu puzzles.
I always forget Kuromasu exists (I think because I associate the clue format with Cave and the shading format with Heyawake) and then whenever it pops up somewhere I’m pleasantly surprised that it does. Looking forward to more of it in the next Quarterly.
On a related note, can I make a request for a “rules” category over in the sidebar, possibly under Other Posts? I’ve been using the weekly PDFs over the last few weeks to fill time during my commute to the capitalism mines, and sometimes if you haven’t seen a genre for a while (or, for instance, used to seeing something like Cave by one of its 78 other names) it can take a bit of tedious searching trying to find out what you’re actually supposed to be doing.
We used to keep separate links for the puzzle styles and the rules and info pages but then the sidebar got very very long. Each puzzle has an embedded link in the rules part of the post that should get you what you want for now. If (when) we do an update to the site that does not have the blog be the user experience for puzzle exploration, we’ll make sure to highlight the rules better there are well.
Hey David, maybe Eric Fox’ aweseom “rule book” will come in handy for you for the time being?
https://docs.google.com/document/d/11U3UAH6V7k9JTpF_WIKLiREc5KYbJGQP89EUBMLtjW0/edit?usp=sharing
Although ctrl+f Kuromasu yields nothing in this case, you can find it under Kurodoku.