PDF

or solve online (using our beta test of Penpa-Edit tools; use Tab to go between number entry and shading modes)

This is a “Franken-Friday” puzzle variation.

Theme: Crypt-oceanography

Rules: Standard Nurikabe rules, except the size of each island has been encrypted. Each letter in this puzzle stands for a different positive integer, which must be determined while solving the puzzle. (Formatting note: space has been left in the cells for you to write the actual number values beneath each letter.)

Answer String: Enter the length in cells of each of the black segments (the unnumbered, connected “ocean”) from left to right for the marked rows, starting at the top. Separate each row’s entry from the next with a comma.

Time Standards (highlight to view): Grandmaster = 10:00, Master = 15:00, Expert = 30:00

Solution: PDF

PDF

or solve online (using our beta test of Penpa-Edit tools)

This is a “Twisted Tuesday” puzzle variation.

Theme: Unique Islands

Rules: Standard Nurikabe rules. Also, each island shape must be unique. This means that no two islands, including rotation and/or reflection of the shapes, can be superimposed.

Answer String: Enter the length in cells of each of the black segments (the unnumbered, connected “ocean”) from left to right for the marked rows, starting at the top. Separate each row’s entry from the next with a comma.

Time Standards (highlight to view): Grandmaster = 4:15, Master = 6:00, Expert = 12:00

Solution: PDF

PDF

or solve online (using our beta test of Penpa-Edit tools)

Theme: Our 72nd prescription. But who’s counting?

Rules: Standard Nurikabe rules.

Answer String: Enter the length in cells of each of the black segments (the unnumbered, connected “ocean”) from left to right for the marked rows, starting at the top. Separate each row’s entry from the next with a comma.

Time Standards (highlight to view): Grandmaster = 7:30, Master = 10:30, Expert = 21:00

Solution: PDF

PDF

or solve online (using our beta test of Penpa-Edit tools)

Theme: Rubber Band – the set of middle clues will stretch your mind a bit.

Rules: Standard Nurikabe rules.

Answer String: Enter the length in cells of each of the black segments (the unnumbered, connected “ocean”) from left to right for the marked rows, starting at the top. Separate each row’s entry from the next with a comma.

Time Standards (highlight to view): Grandmaster = 2:15, Master = 3:00, Expert = 6:00

Solution: PDF

Second in a series with puzzle solving tips. This time, Nurikabe solving tips for last Friday’s puzzle.

A few simple Nurikabe rules will get you through most of the puzzles quite fast; but some of these rules are uncommon enough that you mainly learn them from solving rare puzzles like ours.

(more…)

PDF

or solve online (using our beta test of Penpa-Edit tools)

Theme: Nurikabe Time; don’t wait for the 13th hour to figure out where all the clock islands go.

Rules: Standard Nurikabe rules.

Answer String: Enter the length in cells of each of the black segments (the unnumbered, connected “ocean”) from left to right for the marked rows, starting at the top. Separate each row’s entry from the next with a comma.

Time Standard: Nurikabe Master = 3:00, Expert = 9:00, Novice = 30:00

Solution: PDF and solving video; advice on solving this puzzle has also been posted in “Ask Dr. Sudoku #2“.

PDF

or solve online (using our beta test of Penpa-Edit tools)

Theme: Imbalance – the lower-left is slightly heavier than the upper-right, and is distributed less evenly, affecting the solve.

Rules: Standard Nurikabe rules.

Answer String: Enter the length in cells of each of the black segments (the unnumbered, connected “ocean”) from left to right for the marked rows, starting at the top. Separate each row’s entry from the next with a comma.

Time Standard: Nurikabe Master = 1:45, Expert = 5:15, Novice = 17:30

Solution: PDF

PDF

or solve online (using our beta test of Penpa-Edit tools)

Theme: Twin Islands

Rules: Standard Nurikabe rules.

Answer String: Enter the length in cells of each of the black segments (the unnumbered, connected “ocean”) from left to right for the marked rows, starting at the top. Separate each row’s entry from the next with a comma.

Time Standard: Nurikabe Master = 1:00, Expert = 3:00, Novice = 10:00

Solution: PDF