Cave by Palmer Mebane
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: Logical
Author/Opus: This is the 27th puzzle from our contributing puzzlemaster Palmer Mebane.
Answer String: Enter the length in cells of each of the cave segments from left to right for the marked rows, starting at the top. Separate each row’s entry with a comma.
Time Standards (highlight to view): Grandmaster = 4:30, Master = 7:00, Expert = 14:00
Solution: PDF
Note: Follow this link for other classic Caves. If you are new to this puzzle type, here are our easiest Cave Puzzles to get started on.
06:32.
That was amazing; the opening was wonderful. Is the intended break-in around bottom-left?
The intended break-in is in the bottom-left and is summarized as “7+6 is not 9+5”. The same thing works on the top-right, but not as cleanly.
Yes, exactly. I spotted that one pretty quickly actually; probably failing the Grandmaster time somewhere else.
I am somewhat curious about the solve path on this one as well. I got it through with a little trying here and there, but the top right ended up a bit of a mess.
The bottom left is definitely a strong break-in. You can quickly mark 3 out of 4 of those “X” squares as part of the cave and a little thought fills in the fourth as NOT cave, which gets you a lot of progress. There’s also a bit you can do up by the 7 at the top right away, and it connects up to get you much of the left side (including a wall area that needs to escape getting boxed in, which becomes important). You can pretty much push out from there near the center of the puzzle and get much of the bottom right. The top right was one of the last things to fill in, forced by some things coming up from below it.
22:12