Formed Cave by Serkan Yürekli
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: Clue Symmetry and Logic
Author/Opus: This is the 198th puzzle from our contributing puzzlemaster Serkan Yürekli.
Rules: Standard Cave rules; also, all groups of cells outside the Cave must be formed out of different arrangements of exactly five cells (i.e., different pentominoes). Pentomino shapes may be reflected or rotated, but they cannot repeat or touch each other. Not all pentominoes need to appear.
This example uses four cell regions (i.e., tetrominoes) within the same rules.
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 = 6:45, Master = 11:45, Expert = 23:30
Solution: PDF
Note: Follow this link for other Cave variations and this link for other classic Caves. If you are new to this puzzle type, here are our easiest Cave Puzzles to get started on. More Cave puzzles can be found in The Art of Puzzles and in Roger Barkan’s Colossal Cave Collection.