Dr. Sudoku Prescribes #96 – Nurikabe (Cipher)

Nurikabe by Thomas Snyder

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

Dr. Sudoku Prescribes #77 – Nurikabe (Unique Islands)

Nurikabe by Thomas Snyder

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

Dr. Sudoku Prescribes #72 – Nurikabe

Nurikabe by Thomas Snyder

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

Sunday Surprise #1 – Contest Submissions

In addition to FoxFireX’s incredible sudoku gift that he made for someone’s birthday (some puzzles are meant to keep more private), we got three other submissions for our first Hidden Contest. We’re posting them here in increasing order of difficulty.

First up is an “Anti-Symmetry” Nurikabe from Giovanni P. where every clue that is odd/even has an even/odd clue in the corresponding symmetric place. Standard Nurikabe rules are all you need for this challenge.

Nurikabe by Giovanni P.

Solution image

 

Next up is a real RARITY for this website, a Shakashaka. For the general rules, we’ll direct you to Nikoli.com where the puzzle originated. Here, Bryce Herdt has made a cipher version of the puzzle. The letters AIRTY each stand for a different number from 0 – 4 which the solver must determine.

Cipher Shakashaka by Bryce Herdt

Solution image

 

Finally, the hardest of the bunch, is an intriguing variation called “Sudoku Slitherlink” by its designer Scott Handelman. In addition to standard Slitherlink rules, a different number from 0-3 must go into each green cell. No number in a green cell can repeat in that row or column. As Scott warns, this is one of the hardest puzzles he’s constructed and, from his original post, he’s “still kinda shocked that the middle just kinda ‘works'”.

Sudoku Slitherlink by Scott Handelman

Solution image

 

All of these puzzles are grouped in this single PDF.

If you enjoy these puzzles, please comment here and say so, thanking each of the authors. As contest entries, these didn’t go through editorial review (except making sure there was a single answer), but we found them all quite interesting and worthy of being some of the first puzzles from other authors to appear on this web-site. We’re considering keeping Sunday open for “guest” submissions each week from new puzzle authors. And once we get through a stack of puzzle submissions for The Art of Puzzles, more authors will be appearing throughout the week too.

Dr. Sudoku Prescribes #61 – Nurikabe

Nurikabe by Thomas Snyder

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

Ask Dr. Sudoku #2 – Take Less Time for Nurikabe Time?

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.

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Dr. Sudoku Prescribes #11 – Nurikabe

Nurikabe Time by Thomas Snyder

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“.

Dr. Sudoku Prescribes #9 – Nurikabe

Nurikabe by Thomas Snyder

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

Dr. Sudoku Prescribes #7 – Nurikabe

Nurikabe by Thomas Snyder

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