Battleships (Observers) by Bram de Laat
or solve online (using our beta test of Penpa-Edit tools; use tab to alternate between ship placement and shading modes. In ship placement mode, right click gives sea, left click gives circle/square, left click and drag for rounded ships.)
Theme: Clue Symmetry and Logic
Author/Opus: This is the 6th puzzle from guest contributor Bram de Laat.
Rules: Standard Battleships rules. Also, the clues indicate the total number of white cells visible from that cell in the same row/column, not including the cell itself. The view of cells is blocked by ships. The following example image may help:
Answer String: For each row from top to bottom, enter the number of the first column from the left where a ship segment appears (enter both digits if a two-digit number). If the row is empty, enter 0. Enter these numbers as a single string with no separators.
Time Standards (highlight to view): Grandmaster = 8:30, Master = 13:30, Expert = 27:00
Solution: PDF
Note: Follow this link for more variations on Battleships and this link for classic Battleships. If you are new to this puzzle type, here are our easiest Battleships to get started on.
10:36.
Tough thing to crack, but worth all of it.
I struggled a bit with 2 (implicit ?) rules :
1) Gur ivrj bs pryyf vf ABG oybpxrq ol bgure pyhr pryyf (hayvxr pnir chmmyrf).
2) Pyhr pryyf pnaabg pbagnva fuvc frtzragf.
Was it intended to leave those rules unmentioned ?
Using the example it can easily be proven they both apply, because otherwise :
1) nyy pyhrf va gur rknzcyr jbhyq unir orra gbb uvtu
2) gurer jbhyq or na nygreangr fbyhgvba gb gur rknzcyr (jvgu gur qrfgeblre ubevmbagny va gur gbc evtug pbeare)
Re your note #1, clue cells in cave puzzles don’t block each others’ views.
I like how the three largest ships came last.
This had a certain similarity to solving a Cave puzzle, which meant it took me a while to break my habit of assuming the clue numbers included the cells themselves.