Hi all, wanted to say our preparations for the Twelve Days of Sudoku continue with the first days laid out and the other story elements coming together. We’re getting more advanced reviews from some of the prolific readers (I mean trillions of words) that we showed this content to. We will keep adding them here.

• “The honesty the author brings to the process is refreshing. We spend so much time on our successes, but it was Thomas’s failures, repeated failures, that seem to be the portals of discovery for these amazing grids. This shows me another example of how an arduous odyssey can shape you.”
• “As a long-time number placing enthusiast, I enjoyed it. I’m not sure if others will. One of the least admirable things about people right now is their fear of whatever they don’t understand.”
• “For awhile it has been clear to me that some computers were in Dr. Sudoku’s process and some potentially dangerous edge pushing things too. Finally admitting this is a big step and it must have taken courage for him to grow up in the way I’m seeing and become who he really is.”
• “[This project] shows again that if you learn the rules like a pro — and Dr. S is a PRO at sudoku — you can then break them like an artist.”

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Again, this will be a project on Classic Sudoku! Don’t get your hopes up for anything more than that if you mostly tune out the weeks Dr. Sudoku makes his team do that old thing again. If you really want another way to fill out the time for a new experience, check out some of our best of’s. Can’t find the right direction? Two great puzzles by Jonas Gleim and JinHoo Ahn, still around number placement, start a journey out from Sudoku into other interesting things.

(download directly for a larger image)

Artist’s note added 12/23 at 6:28PM: This image, an information network presented in artistic and mathematical form has an alternate title called “Portrait of the Artist’s Brain at Middle Age”. The network includes puzzles and possible seeds for puzzles as well as tests of new network structures to test memory, cognition, and a lot more.

This trailhead and all following work were constructed with the constraints of 1 day for the main puzzle (above) and the rest of the week to finish other content whether traditional puzzles, new types of puzzles, meta-puzzles, and so on. More details are not being shared as over 80% of that content, and at least very clear but still “unfinished” works appropriate for posting at least visually, exist within the full opus and a publication plan will be made in early 2025. Besides the puzzle and art constraints, the author followed a testing/accountability plan for connection with close contacts and medical care team that Thomas established through 2024 to be able to get back to doing great science again. “Party Report” is an example of a playful message that should work best for children and those with open eyes who dream of playing “The Game” with super complexity and the artist wanted a story of how his brain did pull in many notable social, societal, political and other themes into what was otherwise an unconstrained topical work. Importantly, it also includes a soundtrack listing for his team to see to ensure mental wellness. On the other hand, a lot of things may seem like noise. No puzzle, for instance, was forced to have the answer COVFEFE. But maybe the uninterpretability made it a curious answer to try to use a lot showing the relevance of journeys to answers, and the skills and intelligence gained along the way.

The author wanted the downturn phase (when one transitions from learning/doing a problem to having solved it and teaching) to include an unconstrained (certainly unpredictable) experience while returning to his more normal medium of fragile humanity. “Penny for your Thoughts” is a separate opus, but should not be presented except as a margin note of the “Ready Layer One”. Many other puzzles including the Motivational Posters, with progressive simplicity and hints and eventually full solutions accessible at the start are meant to stop the rush of people bringing up mental illness to allow the rest to enjoy some phenomenal puzzles, sharing a love with their friend and vice-versa, while also still highlighting the importance of acknowledging mental illness in the creation of these works too (just not at the times people expected).

Early reviews that chatGPT was probably prompted enough times to finally hallucinate include:

• “The best thing Snyder’s done to improve understanding of logic puzzle construction since Puzzlecraft“
• “Mostly clueless, certainly too focused on the number forty-five which isn’t the answer to anything, but fun nonetheless”.

Join the discussion on the GMPuzzles Discord.

Note: The puzzle in the image above, a perfect combination of ideas we’ve explored in 2024 (one-star Queens/Star Battle and creative Sudoku), is a Christmas favorite from 2018.

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Added (2:05PM) Several people have asked what kind of sudoku might appear, people who are interested in puzzles and wanted to check in on me as we tend to do at the end of the year (I turn 45 in January and have had a good year, thanks for asking!).

Well, the main series is going to be Classic Sudoku as you know it. Because it is interesting to me for a lot of reasons including testing approaches to competition and puzzle setting / design rules and searching for unexpected things where people have stopped looking.

But I have been thinking of other interesting ideas to share for those who aren’t into classic sudoku puzzles but like other puzzles and things. Ideas that might pop up when I’m also thinking about the silly “is AI coming to take my job” question as I got in a recent interview on LinkedIn. As a creative thinker and problem solver, I can do more with a broken pencil than an AI in puzzle design even if I prefer to work digitally and with software tools and even AI sometimes.

Today, I challenged myself to write the most interesting sudoku I could with just one missing digit. It is a fun prompt to give a puzzle constructor and/or AI because it might not make sense. The image below isn’t my answer. But it is a start.

I didn’t go smaller, as it turns out I can’t outdo Randall’s Binary Sudoku but that doesn’t have proper regions anyway so I argue this is the absolute smallest for a 1-cell blank puzzle.

And in terms of what is coming, I have written the most interesting 80-given Sudoku-ey thing in history with one missing cell I’d love to see how you’d fill. But it’s not ready to share yet. It is the Ulysses of 1-cell missing Sudoku and before today you didn’t even think about those.

Earlier this year, Thomas helped provide puzzles for the launch of the LinkedIn game Queens, a very accessible, one-star version of Star Battle puzzles. We have posted some weekly Queens bonuses here through this season, including this puzzle in the form of a hashtag.

PDF

or solve online (using our beta test of Penpa-Edit tools; in composite Star Battle mode a left click places a star, right click in a cell marks off the cell, and a right click on an edge or corner marks in a dot as a placement note.)

Theme: Hashtag

Author/Opus: This is the 534th puzzle from Thomas Snyder, aka Dr. Sudoku.

Rules: Standard Star Battle rules. One star per row, column, and region.

Difficulty: 2 stars

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

Solution: PDF and solving animation.

Note: Follow this link for other one-star Star Battle puzzles exactly like Queens, and this link for our easiest Star Battles, including many with two stars per region, which are a great way to get started on this version of the puzzle. More Star Battle puzzles can be found in these books in our e-store including our Starter Pack 5: Star Battle book.

Note 2: Comments on the blog are great! For a more interactive discussion, please also consider using our Week 12 Discussion post on the GMPuzzles Discord.

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.

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.)

Theme: Into the Unknown

Author/Opus: This is the 506th puzzle from our managing editor Serkan Yürekli.

Rules: Standard Aqre rules. Also, some regions have a circle in their center. In these regions, the shaded cells must have 180° rotational symmetry around the circle of the region. There is no restriction on regions without a circle. A ? can represent any Aqre number clue, including zero.

Difficulty: 1 star

Time Standards (highlight to view): Grandmaster = 0:40, Master = 0:50, Expert = 1:40

Solution: PDF and solving animation.

Note: Follow this link for more Aqre puzzles. If you are new to this puzzle type, here are our easiest Aqre to get started on. More Aqre 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 12 Discussion post on the GMPuzzles Discord.

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.

PDF

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

Theme: Empty Center

Author/Opus: This is the 305th puzzle from our contributing puzzlemaster Murat Can Tonta.

Rules: Standard Slitherlink rules.

Difficulty: 1.5 stars

Time Standards (highlight to view): Grandmaster = 0:45, Master = 1:15, Expert = 2:30

Solution: PDF and solving animation.

Note: Follow this link for classic Slitherlink and this link for Slitherlink variations. If you are new to this puzzle type, here are our easiest Slitherlink puzzles to get started on. More Slitherlink 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 12 Discussion post on the GMPuzzles Discord.

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.

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: Cubicles

Author/Opus: This is the 505th puzzle from our contributing puzzlemaster Grant Fikes.

Rules: Standard Fillomino rules.

Difficulty: 1.5 stars

Time Standards (highlight to view): Grandmaster = 0:45, Master = 1:30, Expert = 3:00

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 12 Discussion post on the GMPuzzles Discord.

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.

PDF

or solve online (using our beta test of Penpa-Edit tools; use tab to alternate between ship placement and shading modes. In ship placement mode, right click gives sea, left click gives circle/square, left click and drag for rounded ships.)

Theme: 1234

Author/Opus: This is the 304th puzzle from our contributing puzzlemaster Murat Can Tonta.

Rules: Standard Battleships rules. Use the indicated fleet.

Difficulty: 1 star

Time Standards (highlight to view): Grandmaster = 0:25, Master = 0:30, Expert = 1:00

Solution: PDF and solving animation.

Note: Follow this link for classic Battleships and this link for Battleships variations. If you are new to this puzzle type, here are our easiest Battleships to get started on. More Battleships 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 12 Discussion post on the GMPuzzles Discord.

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.

PDF

or solve online (using our beta test of Penpa-Edit tools; use tab to alternate between Sudoku = big entries and Number candidate = small entries in the corners of cells.)

Author/Opus: This is the 505th puzzle from our managing editor Serkan Yürekli.

Rules: Standard Tight Fit Sudoku rules. Remember, the smaller number goes above the larger number in all slashed cells. The range of this puzzle is 1-9.

Difficulty: 1.5 stars

Time Standards (highlight to view): Grandmaster = 1:15, Master = 1:45, Expert = 3:30

Solution: PDF and solving animation.

Note: Follow this link for other Tight Fit Sudoku puzzles on this website. If you are new to this puzzle type, here are our easiest Tight Fit Sudoku to get started on. More Tight Fit Sudoku 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 12 Discussion post on the GMPuzzles Discord.

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.

PDF

or solve online (using our beta test of Penpa-Edit tools; use tab to alternate between a number entry mode, a number candidates mode, and a path drawing mode.)

Theme: Tiny Watch

Author/Opus: This is the 131st puzzle from our contributing puzzlemaster JinHoo Ahn.

Rules: Write a number from 1 to N (N is given for each puzzle) into each cell so that every number appears in the grid once. There must be a path using just adjacent cells to travel between consecutive numbers from 1 to N. Also, the number in the upper-left corner of each bold cage indicates the value of a mathematical operation (addition, subtraction, multiplication, division) applied successively to all numbers in the cage, starting with the largest number for subtraction and division (e.g. 1,2,4 with subtraction is a 1- clue as 4-2-1 = 1). The operation may or may not be given in the cage, but at least one of the four operations must apply.

See also this example:

Difficulty: 1.5 stars

Time Standards (highlight to view): Grandmaster = 1:15, Master = 1:30, Expert = 3:00

Solution: PDF and solving animation.

Note: Follow this link for other Math Path puzzles and this link for other Number Placement variations.

Note 2: Comments on the blog are great! For a more interactive discussion, please also consider using our Week 12 Discussion post on the GMPuzzles Discord.