This was our last week of puzzles for 2020. You can find the set of Fillomino puzzles in this PDF and the solutions are all grouped in this PDF and have also been linked to the individual posts.

We have a solving video for the last two puzzles in the week, including Friday’s Catch-13 Fillomino by Ashish Kumar:

and Saturday’s Fillomino (Checkered) by Jonas Gleim:

We also have a holiday gift for everyone, as we have posted all of our solving videos from before 2020 on Youtube (a total of over 100 walkthroughs)! These are linked to the individual posts if exploring the old archive and also captured on this page. These were filmed with earlier techniques, so some have slightly worse visual/audio quality than we are trying to achieve now, but there is a lot to learn by exploring the videos. I will soon have a new document camera to improve my recording even more, and next year may even try some new kinds of videos like blind solves of competition puzzles and also “basic rules and info” videos for the puzzle styles to better introduce beginners to a new style including its history and basic constraints. Tell us what you’d like to see from future solving videos.

We’ll be taking the next two weeks off to organize our Best of 2020 list and prepare for the start of 2021 puzzles. 2020 has been a full (if challenging) year, with me starting a new job in March and having a lot more responsibilities in leading a large team advancing immunology assays as potential diagnostic tests across diseases. But by adding Serkan Yürekli as our Managing Editor, we together got back to posting 30 straight weeks of puzzles, with at least 2 solving videos each week, and also released 7 new books of puzzles. We have a lot to come in 2021, including more books, the implementation of more routine online solving, a new puzzlemaster and more.

JinHoo Ahn has shared a lot of great web puzzles this year (some that will likely be very competitive for Best of 2020), so I’m quite excited to announce the release of our first book of puzzles from this talented designer, Star Battle.

This book is a collection of 50 Star Battle puzzles, including 15 variations, that have some very nice visual themes and interesting logic. The difficulty ranges from easy to hard, and includes ten 3-star 15×15 puzzles (two of which are variations) and a massive 6-star 30×30 puzzle to finish. Check it out now in our e-store.

We’ll be back later today with the launch of a Star Battle book by JinHoo Ahn, as well as a new book index (by date) for those interested in catching up on all our recent titles.

This past week’s set of LITS puzzles and one variation can be found in this PDF and the solutions are all grouped in this PDF and have also been linked to the individual posts.

We have a solving video for the last three puzzles in the week, starting with the Pirouette LITS by Prasanna Seshadri:

Friday’s Double LITS by Joseph Howard:

and another video for the Saturday LITS by wormsofcan:

This upcoming week, the last of 2020, will feature Fillomino puzzles. We’ll then be taking some time to identify our “Best of 2020” puzzles and will probably use a new voting format this year due to some of the issues with our solving widget. We’ll also have some news for our 2021 plans including what we’ll be doing for online solving next year.

PDF

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

Theme: Pentomino LITS

Author/Opus: This is the 369th puzzle from Thomas Snyder, aka Dr. Sudoku.

Rules: Standard LITS rules.

Difficulty: 1 star

Time Standards (highlight to view): Grandmaster = 0:45, Master = 1:10, Expert = 2:20

Solution: PDF

Note: Follow this link for classic LITS and this link for LITS variations. If you are new to this puzzle type, here are our easiest LITS to get started on. More LITS puzzles can be found in LOTS O’ LITS by Grant Fikes and Prasanna Seshadri, in The Art of Puzzles 2, and in our beginner-friendly collection Intro to GMPuzzles by Serkan Yürekli.

Our next planned e-book will be Star Battle by JinHoo Ahn. We’re putting the finishing touches on it now, and should be posting it this week. So if you enjoyed the most recent week of Star Battle puzzles, please check out this title when it launches.

Last week’s mix of Star Battle puzzles and variations can be found in this PDF and the solutions are all grouped in this PDF and have also been linked to the individual posts.

We have a solving video for the Friday Star Wars variation by JinHoo Ahn:

and another video for the Saturday Star Battle by Thomas Snyder:

This upcoming week will feature LITS puzzles.

PDF

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

Theme: Twisted Keys

Author/Opus: This is the 368th puzzle from Thomas Snyder, aka Dr. Sudoku.

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

Difficulty: 4.5 stars

Time Standards (highlight to view): Grandmaster = 9:00, Master = 18:00, Expert = 36:00

Solution: PDF; a solution video is also available here.

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.

Later today we’ll be sharing a (very hard) sample puzzle from a Killer Sudoku puzzle pack from Serkan Yürekli, which was just added to our e-store. We are experimenting with different sizes for our puzzle titles; while this is a smaller puzzle pack than others, at just 27 puzzles, it is still full of a lot of brain-bending challenge at a $2 price. If you enjoyed the mental arithmetic in this recent Kakuro week, you will certainly enjoy the math and logic needed to get through these Killer Sudoku.

—

Our most recent mix of Kakuro puzzles and variations can be found in this PDF and the solutions are all grouped in this PDF and have also been linked to the individual posts.

We have a solving video for the Thursday Double Kakuro (Invisible) by Grant Fikes:

and another video for the Saturday Kakuro by Prasanna Seshadri:

This upcoming week will feature Star Battle puzzles.

PDF

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

Theme: Five Rooms

Author/Opus: This is the 367th puzzle from Thomas Snyder, aka Dr. Sudoku.

Rules: Standard Kakuro Rules.

Difficulty: 2 stars

Time Standards (highlight to view): Grandmaster = 1:20, Master = 1:45, Expert = 3:30

Solution: PDF

Note: Follow this link for classic Kakuro and this link for Kakuro variations. More Kakuro puzzles can be found in Kakuro and Variations by Serkan Yürekli and in The Art of Puzzles 2.

A few months ago we had a full week of Kurotto puzzles and promised that an e-book would be available later this year with more of this great shading puzzle style. Today we’ve released that e-book, Kurotto by Prasanna Seshadri, and it is one of my favorite books that we’ve published because it takes this puzzle style much further than others have, including with a few new variations from Prasanna.

—

Our most recent mix of Sudoku puzzles and variations can be found in this PDF and the solutions are all grouped in this PDF and have also been linked to the individual posts.

We have a solving video for the Thursday XV Sudoku by Ashish Kumar:

and another video for the Saturday Thermo-Sudoku by Thomas Snyder:

If you prefer to see Simon from Cracking the Cryptic work on this grid, we have that video too:

This upcoming week will feature Kakuro puzzles.

PDF

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

Theme: Clueless

Author/Opus: This is the 366th puzzle from Thomas Snyder, aka Dr. Sudoku.

Rules: Standard Thermo-Sudoku rules.

Difficulty: 4 stars

Time Standards (highlight to view): Grandmaster = 6:15, Master = 10:00, Expert = 20:00

Solution: PDF; a solution video from the author is also available here and another from Cracking the Cryptic is here.

Note: Follow this link for more Thermo-Sudoku puzzles. If you are new to this puzzle type, here are our easiest Thermo-Sudoku to get started on. More Thermo-Sudoku puzzles can be found in The Art of Sudoku 2 and Masterpiece Sudoku Mix 2.