From the Foxger’s Den #9: Slitherlink (Domino)

Slitherlink by Grant Fikes

PDF

or solve online (using our beta test of Penpa-Edit tools; use tab to alternate between edgex mode where left click+drag draws lines and right click marks X’s and a line drawing mode to mark the dominoes.)

This is a “Twisted Tuesday” puzzle variation.

Theme: Double Domino – both domino-based clue groupings, and a domino-based loop.

Rules: Standard Slitherlink rules; also, the interior of the loop must be divisible into dominoes (1×2 rectangles) in at least one way without any overlaps.

Answer String: Enter the length in cells of each of the internal loop 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

Editorial Note: This puzzle is a fair bit more difficult than our usual Tuesday puzzles, but this may be a side effect of the new Twisted Tuesday format.

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 #62 – Sudoku (Seek and Spell)

Sudoku Variation by Thomas Snyder

PDF

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

This is a “Franken-Friday” puzzle variation.

Theme: Mostly Themeless! – Besides elements of symmetry and some patterning in the numbers, the design is focused on the logical solution path.

Rules: Standard Sudoku rules. Clues in the grid represent typical “Seek and Spell/Kanaore” clues; specifically, it must be possible to read each of the numbers listed below the grid by starting at the indicated letter, moving one cell in the direction indicated by the arrow, and then continuing to move one cell at a time up, down, left, or right to complete the number. No cell may be used more than once in a single number’s path, but the same cell can appear in the paths of different numbers.

Answer String: Enter the 3rd column from top to bottom, followed by a comma, followed by the 9th column from top to bottom.

Time Standards (highlight to view): Grandmaster = 7:00, Master = 12:30, Expert = 25:00

Solution: PDF

From the Foxger’s Den #7: Battleships (Yajilin)

Battleships (Yajilin) by Grant Fikes

PDF

or solve online (using our beta test of Penpa-Edit tools; use tab to shift between Battleships placement and line drawing modes.)

This is a “Twisted Tuesday” puzzle variation.

Theme: A Fleet of Clues

Rules: Variation of Battleships rules. Place the fleet of ships in the grid so that no ships touch each other, even diagonally. The grid contains internal clues (a number and an arrow) that show how many ship segments are in the indicated direction. All remaining cells containing neither a ship nor a clue must be able to form a single loop, as in a Yajilin puzzle (see for example here but note the “black square rules” are replaced with battleships placement rules).

Answer String: For each row from top to bottom, enter the number of the first column from the left where a ship segment appears. If the row is empty, enter 0. Enter these numbers as a single string with no separators.

Time Standards (highlight to view): Grandmaster = 2:30, Master = 4:00, Expert = 8:00

Solution: PDF

Mystery TomTom

Mystery TomTom by unknown author

PDF

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

Theme: Guess the author?

Rules: Variation of standard TomTom rules. In these puzzles, the five numbers to enter are not 1-5. In each grid, there are five unknown integers that the solver must determine.

Answer String: Enter the 3rd row from left to right in the left puzzle, followed by a comma, followed by the 3rd row from left to right in the right puzzle.

Time Standards (highlight to view): Grandmaster = 1:00, Master = 1:30, Expert = 3:00

Solution: PDF

**While this was initially not a numbered opus in this author’s work, we are calling it #47 for our site count.

Welcome to Grandmaster Puzzles!

A logo, and a puzzle

PDF

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

Welcome to the new puzzle blog from Thomas Snyder, aka “Dr. Sudoku”, 3-time world sudoku champion and author of many books of puzzles including “The Art of Sudoku”. Here you will find a range of logic puzzles including number placement puzzles (such as Sudoku and TomTom), object placement (such as Battleships and Star Battle), region division (such as Fillomino and Cave), shading (such as Nurikabe and Tapa), path/loop (such as Slitherlink and Masyu) and many more.

Puzzles will get progressively harder throughout the week, so there will be easy puzzles for beginners on Monday and Tuesday to start the week and much harder puzzles by Friday and Saturday. Eventually there will be a random mix of many puzzle types every week, but as I start I will focus on two types each week, with Sudoku and TomTom leading the way. Puzzles will typically post at 9:00 AM Pacific Time.

This puzzle blog will have a few unique features. First, I want to actively track (and reward) the puzzle solvers. At the bottom of each post is a “solved” button. If you enter the correct answer string, your solution will be logged in. Eventually there will be leaderboards, contests, and prizes for people solving the puzzles. So if you solve the puzzles, log your success here. Mark your favorite puzzles too. So if a lot of solvers for example like TomTom over other styles, then you’ll see more of them here — and more TomTom books published.

Each puzzle has a “difficulty” posted too. This is just a recommendation from the expert/World Puzzle Championship level solvers who have helped test all the puzzles. The time has three values: the “Master” time, and then an “Expert” time (3x) and a “Novice” time (10x). Whatever level solver you are, these ratings should give you a sense of how hard a puzzle might be, and also give you a real sense of how well you are solving if you want to time yourself. But don’t start the stopwatch if you are just here for fun!

For any puzzle you really like, click on the tags to the left for more examples. Besides the posted puzzles, I will be releasing books with all of these puzzle styles. For Sudoku and Sudoku Variations and TomTom I already have books available for purchase. For the other styles, new titles like “The Art of Puzzles” will be coming soon.

This will be an exciting project, and I hope to see you visiting here a lot in the future. And if you have any recommendations for new puzzle styles, or want to make your own puzzle contributions here, just email me to start a dialogue.

Rules: The puzzle in this post is in the GMPuzzles logo. This is a Wordoku with a repeated letter so follow standard sudoku rules with a slight twist.

Time Standard: Sudoku Master = 2:30, Expert = 7:30, Novice = 25:00

Answer Check: USING CAPITAL LETTERS, enter the 8th row from left to right, followed by a comma, and then the 5th column from top to bottom (e.g. “GMPUZZLES,GMPUZZLES”)

Solution: PDF