From the Foxger’s Den #11: Masyu

Masyu by Grant Fikes

PDF

or solve online (using our beta test of Penpa-Edit tools in linex mode where left click+drag draws lines and right click marks X’s)

Theme: Logical theme you may encounter when solving

Rules: Standard Masyu rules.

Answer String: Enter the length in cells of the horizontal loop segments from left to right in the marked rows, starting at the top. If the loop only has vertical segments in the marked row, enter 0. Separate each row’s entry with a comma.

Time Standards (highlight to view): Grandmaster = 0:50, Master = 1:15, Expert = 2:30

Solution: PDF

Dr. Sudoku Prescribes #69 – Skyscrapers (Sum)

Sum Skyscrapers by Thomas Snyder

PDF

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

This is a “Twisted Tuesday” puzzle variation.

Theme: Arithmetic Series

Rules: Variant of Skyscrapers rules. The numbers outside the grid represent the sum of the buildings seen in that row or column. For example, if a row is 12534, the clue from the left would be an 8 (1+2+5) and from the right would be a 9 (4+5).

Answer String: Enter the 3rd row from left to right, followed by a comma, followed by the 5th row from left to right.

Time Standards (highlight to view): Grandmaster = 1:30, Master = 2:45, Expert = 5:30

Solution: PDF

Dr. Sudoku Prescribes #68 – Word Search

Word Search by Thomas Snyder

PDF

or solve online (using our beta test of Penpa-Edit tools; use tab to alternate between a line drawing mode and a shading mode.)

Theme: Grandmasters

Rules: Standard Word Search rules.

Answer String: Enter the final message, related to what you are getting today, revealed by solving the puzzle. Enter the answer in all capital letters, with no spaces or punctuation.

Time Standards (highlight to view): Grandmaster = 8:30, Master = 11:30, Expert = 23:00

Solution: PDF

Doctor’s Note – Week 13

Last week saw the release of Puzzlecraft: The Ultimate Guide on How to Construct Every Kind of Puzzle, a really incredible project with Mike Selinker that was an extension of our GAMES Magazine articles that have run for many years (I joined Mike around article #48 when he wanted to write on how to construct Battleships. I’ve been part of the process ever since as we now approach #100). The title seems overly broad, but I challenge anyone to come up with a puzzle style that isn’t covered in the book.

Last week also saw Mike and I finish construction on a book you’ll get to see next year, Tile Crosswords, a word puzzle style that we developed out of the logic puzzle “Crack-It-On” that first appeared at the WPC in Hungary in the late 90s. You might not picture me as someone who fills grids with letters that have a meaning when considered as intact strings, let alone then provides sets of letters outside the grid that also form strings that evoke the sets of letters that are in the grid — certainly if I write about making word grids and cluing them that way it would seem impossible that I even speak English — but it is something I’ve been increasingly finding joy in doing.

The reason I mention all this is to give you some forewarning that over the coming months we may have other puzzle types than just sudoku and abstract logic puzzles here. Just as with the Hidden Contest that ended last week, I intend Grandmaster Puzzles to have all the kinds of puzzles I would like to solve, but with a friendly mix of easy to hard and lots of different genres so that if today is not your cup of tea, then tomorrow probably is. You may only think of me as a logic puzzle constructor, but working with Mike over the last few years has really developed my puzzle-making chops in almost every area.

Whatever puzzles we release here, they should still be worthy in their genres of being called masterpieces.

Sincerely,
Dr. S

Ask Dr. Sudoku #12 – The line must be drawn here

To [guess], or not to [guess], that is the question:

Whether ’tis Nobler in the mind to suffer

The [Twists] and [the Turns] of outrageous [Logic],

Or to take Arms against a Sea of troubles,

And by [guessing] end them….

We’ve had a fair number of lively discussions in the last week, and if nothing else has come out of them at least the comment threading on the site is now noticeably improved. One question that has come up a lot has been around which puzzles need guesswork, here and elsewhere. A lot of solvers, for the sake of speed perhaps, will say they “had to bifurcate” during a solve here, but that has never been required for our puzzles. This week I wanted to (briefly) state my opinions on what I consider to be “logical” puzzles, since I mention frequently that all puzzles will have a single solution that can be reached by logic alone and it is worth contributors and solvers knowing what I mean by that.

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Dr. Sudoku Prescribes #67 – Sudoku

Sudoku by Thomas Snyder

PDF

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

Theme: Logical solving theme

Rules: Standard Sudoku rules.

Answer String: Enter the 5th row from left to right, followed by a comma, followed by the 6th column from top to bottom.

Time Standards (highlight to view): Grandmaster = 6:30, Master = 10:30, Expert = 21:00

Solution: PDF

Note: Follow this link for other classic Sudoku. If you are new to this puzzle type, here are our easiest Sudoku to get started on. More classic Sudoku puzzles can be found in The Art of Sudoku, The Art of Sudoku 2 and in our beginner-friendly collection Intro to GMPuzzles by Serkan Yürekli.

Dr. Sudoku Prescribes #66 – Tapa (Pentomino)

Tapa by Thomas Snyder

PDF

or solve online (using our beta test of Penpa-Edit tools; use tab to shift between shading mode and the composite Yajilin mode where left click marks cells, right click marks dots in cells or X’s on edges, left click+drag draws lines.)

This is a “Franken-Friday” puzzle variation.

Theme: Pentapa

Rules: Standard Tapa rules. Also, the Tapa wall in this puzzle is made using one of each pentomino given below the grid with no overlaps. Rotations and reflections are allowed. (Note: There is no P pentomino here because it would violate Tapa rules).

Answer String: Enter the length in cells of each of the shaded segments 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 = 6:30, Master = 11:00, Expert = 22:00

Solution: PDF

From the Foxger’s Den #10: Fillomino

Fillomino by Grant Fikes

PDF

or solve online (using our beta test of Penpa-Edit tools; use tab to alternate between a composite mode for line/edge drawing and a number entry mode.)

Theme: Parquet

Rules: Standard Fillomino rules.

Answer String: For each cell in the marked rows/columns, enter the area of the polyomino it belongs to. Start with the 5th column, followed by a comma, followed by the 7th column.

Time Standards (highlight to view): Grandmaster = 1:30, Master = 2:00, Expert = 4:00

Solution: PDF

Note: Follow this link for other classic Fillomino and this link for more variations on Fillomino puzzles. If you are new to this puzzle type, here are our easiest Fillomino puzzles to get started on.

Dr. Sudoku Prescribes #65 – Star Battle

Star Battle by Thomas Snyder

PDF

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

Theme: Broken Window

Rules: Standard Star Battle rules. Two stars per row, column, and region.

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

Time Standards (highlight to view): Grandmaster = 3:30, Master = 5:00, Expert = 10:00

Solution: PDF

Note: Follow this link for other classic Star Battles and this link for Star Battle variations. If you are new to this puzzle type, here are our easiest Star Battles to get started on. More Star Battle puzzles can be found in The Art of Puzzles, in the book Star Battle by JinHoo Ahn, and in our beginner-friendly collection Intro to GMPuzzles by Serkan Yürekli.

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