Nanro (Triangle) by Martin Ender, inspired by “Composition with Grid 4: Lozenge Composition” by Piet Mondrian

[Editor’s Note / context: For those looking for more puzzles here besides Sudoku, we still don’t have new plans for this year. We need more focus on the large efforts we have underway and in general that still means on Sudoku and staying healthy until we can grow the team. But as editors, we too miss the unexpected submissions that surprise and delight.]
[Now you can’t just commission a “museum series” of unforgettable grids, but we were delighted by what happened here. A few months ago Thomas shared a photo (far below) he takes every time he visits the Philadelphia Museum of Art, thinking this grid by Mondrian will always deserve a puzzle when he can get to it. Without expectation of anything appearing, Martin delivered a tremendous fit for the grid, that used its elements fully, that added its own theme with just three kinds of givens that left us a bit shocked. We’re pleased to share now as a bonus for all to enjoy.]

Nanro (Triangles) by Martin Ender

PDF

or solve online (using our beta test of Penpa-Edit tools; use the tab key to alternate between shading and number entry modes)

Author/Opus: This is the 18th puzzle from guest contributor Martin Ender.

Rules: Label some cells with numbers to form a single connected group of labeled cells; no gridpoint is entirely surrounded by numbered cells. Each bold region must contain at least one labeled cell. Each number (including any given numbers) must equal the total count of labeled cells in that region. Two cells containing the same number may not share a thick border.

Difficulty: 4 stars

Time Standards (highlight to view): Grandmaster = 10:00, Master = 25:00, Expert = 50:00

Solution: PDF and solving animation.

Note: Follow this link for Nanro puzzles on this website and this link for variations on Nanro puzzles. If you are new to this puzzle type, here are our easiest Nanro Puzzles to get started on. More Nanro puzzles can be found in A Number o’ Nanro by Prasanna Seshadri.

Note 2: Comments on the blog are great! For a more interactive discussion, please also consider using our General Blog Puzzle Discussion on the GMPuzzles Discord.

Thomas with Mondrian grid

Renban / Little Killer Sudoku by Mr.Menace

(This post is the first in a new: “Cryptic Sudoku series”.)
This brilliant puzzle by Mr.Menace was first created in 2021 and is now being licensed to share on GMPuzzles as part of our Cryptic Sudoku series, with a YouTube discussion as well.

Renban Little Killer Sudoku by Mr.Menace

PDF

or solve online (using SudokuPad)

Theme: Renban ModE

Author/Opus: This is the 2nd puzzle from guest contributor Mr.Menace.

Rules: Standard Sudoku rules (insert a number from 1 to 9 into each cell so that no number repeats in any row, column, or bold region). Numbers along each line must form a non-repeating consecutive set, in any order. (For example, a 4-cell Renban line could be 4352, but not 5679 or 2312.) Also, numbers along the indicated diagonals must sum to the given total outside the grid. Numbers can repeat on the diagonals if not violating standard Sudoku rules.

Difficulty (highlight to view): 4 – 4.5 stars

Thomas time (from video with talking): 13:21

Solution: PDF and also covered as part of this YouTube video.

Note: Follow this link for other less common variations of Sudoku. For some easier Sudoku like this check out the Genuinely Approachable Sudoku (GAS) series.

Note 2: Comments on the blog are great! For a more interactive discussion, please also consider using our Twelve Months of Sudoku? post on the GMPuzzles Discord. Not a member of the Discord? Click this link for basic access.

Mini-Sudoku by Mr.Menace

(This post is part of: “A Story of Self-setting Sudoku”.)
Eventually, all sudokus will set themselves. Even given two clear options, it’s still up to the setter to control the paths from getting out of hand. Otherwise, the system might get stuck before finishing.

Mini-Sudoku by Mr.Menace

PDF

or solve online (using SudokuPad)

Theme: System Halt 1: A Sequence Got Stuck

Author/Opus: This is the 1st puzzle from guest contributor Mr.Menace.

Rules: Insert a number from 1 to 9 into each white cell so that no number repeats in any row, column, or bold region.

Difficulty (highlight to view): 2 stars

Time Standards (highlight to view): Grandmaster = 1:15, Master = 2:00, Expert = 4:00

Solution: PDF

Note: Follow this link for 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.

Note 2: Comments on the blog are great! For a more interactive discussion, please also consider using our Twelve Months of Sudoku? post on the GMPuzzles Discord. Not a member of the Discord? Click this link for basic access.

Just One Cell Classic Sudoku by Gliperal

This is the second of two puzzles posting today in this style.

Just One Cell Classic Sudoku by Gliperal

PDF

or solve online in Penpa, or also solve online in SudokuPad as a new option (note: highly recommended to turn off “Mark Solved Digits” option if you use that in SudokuPad).

Author/Opus: This is the 1st puzzle from guest contributor Gliperal.

Rules: This Sudoku does not have a unique solution for the full grid (it actually has a large number of solutions), but there is exactly one cell in which a number can be logically placed that is fixed across all solutions. Find this cell and its unique value.

This puzzle follows Classic Sudoku rules, so no number repeats in any row, column, or bold region.

Time Standards (highlight to view): This competition had 1-point (easy), 2-point (medium), 3-point (hard), or higher value puzzles. This was worth 5 points (extreme category), roughly 5+ minute target.

Solution: PDF

Note: Follow this link for other Just One Cell Sudoku.

Note 2: Comments on the blog are great! For a more interactive discussion, please also consider using our Just One Cell Sudoku Discussion post on the GMPuzzles Discord. Not a member of the Discord? Click this link for basic access.

The king is dead, long live the king

On 25/01/19 at around 5:50 AM, mars opened the second gate and recovered the “coin”, an identification bracelet, left hidden in a tree where olives and oranges cross near a red hovse.

Alongside the “coin” was this hand-written message: “While our diagnoses may be a part of our identities, they cannot be the sole things that define us. I’ve lived too long in fear of mine, when I should still be inspired by what I can do with brilliant minds around me when I try. Knowing that fear is the mind-killer, I leave behind this bracelet of the past, and I go back to pushing the boulder up the hill. You don’t have to imagine me happy. The boulder feels much lighter this time and I know I can get it higher than ever before. See you at the top.”

———-

Congrats to mars for winning the first Grandmaster Puzzle Hunt (see this post for instructions and some trailheads), and gaining responsibility over this blog for at least the next year. Unfortunately there aren’t many “riches” from running GMPuzzles, so if it turns out mars is / are rational actor(s), and not an unduly sentimental patron of puzzles like former management, most projects like subscriptions will be “paused” due to excessive costs. There may still be some puzzles posted here as bonuses, but for now we expect a bit of a gap as mars assesses things. Let’s all celebrate the end of a challenging month of puzzles and other content that will take awhile to fully understand.

Tapa by Nate Perkins

This is a free “warm-up” puzzle; Season 4 subscribers will see today’s main puzzle in the same style posted at 9:05 AM PT.

Tapa by Nate Perkins

PDF

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

Theme: One-off

Author/Opus: This is the 6th puzzle from guest contributor Nate Perkins.

Rules: Standard Tapa rules.

Difficulty: 1 star

Time Standards (highlight to view): Grandmaster = 0:45, Master = 1:00, Expert = 2:00

Solution: PDF and solving animation.

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

Note 2: Comments on the blog are great! For a more interactive discussion, please also consider using our Week 9 Discussion post on the GMPuzzles Discord.

End of Season 4 Preview Week

We hope you enjoyed the recent “preview week” of puzzles for Season 4 of Grandmaster Puzzles.

Click here for a PDF of all the preview week puzzles.
Click here for a PDF of all the solutions.

Starting tomorrow will be the first subscribers-only week of this season, featuring Star Battle puzzles and variations. The easier warm-up puzzles will still be here for everyone to see but the main blog puzzles and the interesting Sunday Specials will be for subscribers only. Overall there will be 12 weeks and about 100 subscriber only puzzles in Season 4. Subscriptions can be purchased in our e-store at this link.

We also have a special deal for people who purchase before the end of September: Get (a maximum of) $4 off any other book/subscription on the GMPuzzles store by adding that item to the same cart when you purchase Season 4. This is a great way to pick up another GMPuzzles book, or to catch up on prior subscriptions where you’ll be able to get access to all puzzles and blog posts right away.

Consecutive Pairs Sudoku by Salih Alan

Consecutive Pairs Sudoku by Salih Alan

PDF

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

Theme: Hourglass

Author/Opus: This is the 31st puzzle from guest contributor Salih Alan.

Rules: Standard Consecutive Pairs Sudoku rules. (If a gray circle is given between two adjacent cells, then the two numbers in those cells must be consecutive. Note not all gray circles are given; adjacent cells without a circle may contain either consecutive numbers or nonconsecutive numbers.)

Difficulty: 4.5 stars

Time Standards (highlight to view): Grandmaster = 6:45, Master = 15:00, Expert = 30:00

Solution: PDF and solving animation.

Note: Follow this link for Consecutive Pairs Sudoku puzzles on this website. If you are new to this puzzle type, here are our easiest Consecutive Pairs Sudoku to get started on. More Consecutive Pairs Sudoku puzzles can be found in these books in our e-store.

Note 2: Comments on the blog are great! For a more interactive discussion, please also consider using our week-0-discussion thread on the GMPuzzles Discord. If you are not yet part of this Discord community, use this link.

Consecutive Pairs Sudoku by Akash Doulani

Consectuive Pairs Sudoku by Akash Doulani

PDF

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

Theme: All Round Symmetry

Author/Opus: This is the 20th puzzle from guest contributor Akash Doulani.

Rules: Standard Consecutive Pairs Sudoku rules. (If a gray circle is given between two adjacent cells, then the two numbers in those cells must be consecutive. Note not all gray circles are given; adjacent cells without a circle may contain either consecutive numbers or nonconsecutive numbers.)

Difficulty: 2 stars

Time Standards (highlight to view): Grandmaster = 2:45, Master = 3:30, Expert = 7:00

Solution: PDF and solving animation.

Note: Follow this link for Consecutive Pairs Sudoku puzzles on this website. If you are new to this puzzle type, here are our easiest Consecutive Pairs Sudoku to get started on. More Consecutive Pairs Sudoku puzzles can be found in these books in our e-store.

Note 2: Comments on the blog are great! For a more interactive discussion, please also consider using our week-0-discussion thread on the GMPuzzles Discord. If you are not yet part of this Discord community, use this link.

Fillomino (Non-consecutive) by Freddie Hand

Fillomino (Non-consecutive) by Freddie Hand

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.)

Author/Opus: This is the 16th puzzle from guest contributor Freddie Hand.

Rules: Variation of Fillomino rules. No two polyominoes with the same area, or with areas that differ by one, can share an edge.

Difficulty: 3.5 stars

Time Standards (highlight to view): Grandmaster = 3:45, Master = 6:30, Expert = 13:00

Solution: PDF and solving animation.

Note: Follow this link for classic Fillomino and this link for Fillomino variations. If you are new to this puzzle type, here are our easiest Fillomino puzzles to get started on. More Fillomino puzzles can be found in these books in our e-store.

Note 2: Comments on the blog are great! For a more interactive discussion, please also consider using our week-0-discussion thread on the GMPuzzles Discord. If you are not yet part of this Discord community, use this link.