[This is a repost from our archives with new notes at the top (original post here): In this Star Battle, the second posted on the site, a common cage shape theme is used multiple times to lead to a logical solving path.]

PDF

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

Theme: Crossed Crosses

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

Estimated Difficulty*: 2 stars

Time Standards (highlight to view): Grandmaster = 1:15, Master = 2:30, Expert = 5:00

Solution: PDF

Note 2: 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 books Star Battle and Star Battle 2, and in our beginner-friendly collection Intro to GMPuzzles by Serkan Yürekli.

We’re starting off our six part series of Best of 2022 posts with Sudoku, a puzzle category with 59 entries throughout the year as well as a place in many of our e-book releases including the Masterpiece Sudoku Mix series and the Grandmaster Puzzles Quarterly series.

As in years past, we selected the top Sudoku by reviewing FAVE votes, web comments, and tested comments. All of these puzzles are gathered in this PDF file.

Our first “best of” puzzle goes to a challenging Classic Sudoku by Ashish Kumar that had some unusual steps to get to the finish.

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

Another top sudoku was the t-shirt puzzle by Thomas Snyder for the United States team at the recent World Sudoku and Puzzle Championships, with a very clean theme not needing any given digits.

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

Guest constructor Jonas Gleim made a fantastic combination of Arrow and Thermo-Sudoku puzzles with this “Compass” Sunday Stumper from May that received a lot of favorite votes.

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

A Thermo-Sudoku from Kishore Kumar Sridharan took the second overall Sudoku spot, with a “weighty” theme from the given dumbbell.

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

Surprisingly, the top puzzle for the year was a new variation, Multiples Sudoku, and the “example” puzzle that Thomas Snyder wrote for the Sudoku Grand Prix round from the United States. We haven’t featured those puzzles here yet, but the fresh logic surrounding the two-digit placements got the attention of many solvers, earning the most votes to be our best of 2022 Sudoku.

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

[This is a repost from our archives with new notes at the top (original post here): Symmetrically marked cells are one of the easier themes to achieve with Thermo-Sudoku, and in this puzzle the double zeroes highlight a few different kinds of logic to get to the unique solution.]

PDF

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

Theme: Double Zeroes

Rules: Standard Thermo-Sudoku rules.

Estimated Difficulty*: 2 stars

Time Standards (highlight to view): Grandmaster = 2:15, Master = 3:30, Expert = 7:00

Solution: PDF

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 in Masterpiece Sudoku Mix 2.

[This is a repost from our archives with new notes at the top (original post here): Star Battle, which was originally designed by Hans Eendebak for the 2003 World Puzzle Championship, is one of our favorite object placement styles. The region constraints and no touching constraints lead to a lot of different logic. While there are computer-generated versions of this style in major newspapers now, the hand-crafted themes and logical flows of this puzzle are what we look for with any Grandmaster Star Battle.]

PDF

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

Theme: Downward Spiral

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

Estimated Difficulty*: 1.5 stars

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

Solution: PDF

Note 2: 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 books Star Battle and Star Battle 2, and in our beginner-friendly collection Intro to GMPuzzles by Serkan Yürekli.

[This is a repost from our archives with new notes at the top (original post here): Greater than/less than constraints can lead to good forcing chains in different number puzzles. However, I’ve never been a fan of using lots of < and > shapes (particularly when rotated 90 degrees) as that notation only works well across pairs of cells and not across chains of connected cells. I created Thermo-Sudoku as a new presentation method to make multi-cell constraints more easily seen and allow for graphically interesting themes. I first developed the style and name while planning for the book Mutant Sudoku with Wei-Hwa Huang, with imagery of a “melted thermometer in the boiling sudoku solution being poured out on paper” as the first mutation caused by Dr. Sudoku’s mistakes in the lab.]

PDF

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

Theme: Grandmaster Puzzles (the G and P shapes in the corners)

Rules: Standard Thermo-Sudoku rules. Range is 1-6.

Estimated Difficulty*: 1 star

Time Standards (highlight to view): Grandmaster = 0:40, Master = 1:00, Expert = 2:00

Solution: PDF

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 in Masterpiece Sudoku Mix 2.

Our latest “Smashing the Sudoku” video covering the hard Nurikabe and Tight Fit puzzles from last week is now online.

After some extreme weather that caused power outages and then some other challenges, we’re back on track to get through our January tasks including announcing the Best of 2022 puzzles and releasing some bonus Microsoft Puzzle Hunt content. Keep a watch here for those updates and also for the start of discussing our 2023+ plans for the site in the coming weeks.

Puzzle PDF

Author/Opus: This is the 431st puzzle from Thomas Snyder, aka Dr. Sudoku.

Hints: (in rot13):
1. What are these strange puzzle types? Gurl’er glcrf bs ybtvp chmmyrf. Vs lbh frnepu sbe gurve anzrf ba guvf fvgr, gurer ner qrfpevcgvbaf, ubj gb fbyir thvqrf, naq rira ivqrbf.
2. How do I get started? Frira chmmyr glcrf jvgu whfg fvk tevqf? Lbh’yy svefg jnag gb svther bhg ubj rnpu tevq pna havdhryl fbyir nf whfg bar bs gubfr chmmyr glcrf, naq guebhtu fbyivat gur chmmyr vqragvsl gur ? inyhrf juvpu, va nyy pnfrf, ner abg arrqrq gb svaq gur fbyhgvba rkprcg sbe gur snpg gurl ner n pyhr pryy naq va fbzr fglyrf pnaabg or funqrq bire be orybat jvgu nabgure pyhr va na vfynaq/erpgnatyr.
3. How do I figure out which puzzle is which type? Gur tevqf jvgu gur srjrfg pyhrf ner Ahevxnor naq Fuvxnxh naq gur tevq jvgu gur zbfg pyhrf vf n Svyybzvab. Gur erznvavat guerr ner fcyvg npebff Pnir, Xhebznfh, naq Xhebggb. N xrl ybtvpny qrqhpgvba sbe Pnir vf gung lbh pna arire svyy va n purpxreobneq yvxr 2k2 cnggrea bs oynpx naq juvgr fdhnerf (be ryfr lbh jvyy ivbyngr gur pbaarpgvivgl ehyrf). Fb sbphf ba fbzr bs gur 2 pyhrf jvgu qvntbanyyl nqwnprag arvtuobef gb vqragvsl juvpu chmmyr zhfg or gur Pnir.
4. Which puzzle is which type? Sebz hccre yrsg gb ybjre evtug, gur chmmyr glcrf ner: Ahevxnor, Xhebggb; Xhebznfh, Pnir; Svyybzvab; Fuvxnxh.
5. How do I solve the bottom one on the left? Gur obggbz bar ba gur yrsg vf n Svyybzvab chmmyr. Vg znl or n irel uneq chmmyr gb fbyir hagvy lbh erpbtavmr gur tvira pyhrf nyernql nppbhag sbe ng yrnfg 30 (fvk svirf) + 30 (svir fvkrf) + 21 (guerr friraf) pryyf jbegu bs cbylbzvab tebhcf.
6. How do I get a final answer? Gur dhrfgvba znexf va gur qvssrerag tevqf jvyy fgnaq sbe {1,1,6}, {1,2,3,4}, {2,2,3,4}, {2,3,3,5}, {3,3,4,6}, naq {5,6,6,7} juvpu znl uryc vs lbh unir whfg n pbhcyr yrsg hafbyirq. Hfr gurfr inyhrf gb perngr gur 7gu zvffvat chmmyr, gura fbyir vg.

Solution: PDF

Answer String: Enter the final answer (a word or phrase) in ALL CAPITAL LETTERS without spaces to confirm. There may be intermediate answer phrases that are not the final answer; our answer checker is not able to send the message “Keep going” like the Microsoft Hunt solving software does so if you do not see what you expect, treat it like “Keep going” and potentially send an email to us or watch out for hints.

[Note: The remaining two Microsoft Puzzle Hunt puzzles will be released on upcoming future Sundays (starting Jan 29) since these are involved puzzles to solve and harder than our usual weekday content.]

[More comments about the site below; for now, here is the first of four puzzles that I wrote for last year’s Microsoft Puzzle Hunt. Our “Binary Earth” round had paired puzzles that would look similar with a “large thing” and a set of “small things” to look at. This is the easiest puzzle of the set, entitled EXPLORER. Just as at the Microsoft Puzzle Hunt, it is presented solely as a PDF with no specific instructions. I will add hints each day as I also release the other 3 puzzles I wrote for that Hunt this week.]

Puzzle PDF

Author/Opus: This is the 430th puzzle from Thomas Snyder, aka Dr. Sudoku.

Hints (in rot13):
1. What is this puzzle? Gur zrffntr vf qrfpevovat n “Zvarfjrrcre (Cragbzvab)” chmmyr naq gur hahfhny sbeznggvat jvyy or vzcbegnag nsgre fbyivat gung chmmyr (ohg abg orsber).
2. How do I get started? Orpnhfr cragbzvabrf unir znal pbaarpgrq pryyf, fbzr bs gur zbfg xrl pyhrf gb ybbx ng ner gur 1’f va qvssrerag ertvbaf bs gur tevq nf lbh pbafvqre funcrf. Fbzr bs gur cragbzvabrf ng gur gbc ner gur Y, C, naq M juvyr fbzr bs gur cragbzvabrf ng gur obggbz ner gur V, A, naq I.
3. I finished the first part. What now? Rnpu cragbzvab unf n ynory, naq gung zvtug uryc lbh xabj jurer gb ybbx gb svaq bhg jung gb qb ng gur raq.
4. How do I get a final answer? Ernq gur yrggref haqre gur cragbzvab ynoryf gb trg n 12-yrggre vafgehpgvba, gura sbyybj gung vafgehpgvba jvgu gur cragbzvabrf, znxvat ab bgure punatrf, gb erirny gur nafjre.

Solution: PDF

Answer String: Enter the final answer (a word or phrase) in ALL CAPITAL LETTERS without spaces to confirm. There may be intermediate answer phrases that are not the final answer; our answer checker is not able to send the message “Keep going” like the Microsoft Hunt solving software does so if you do not see what you expect, treat it like “Keep going” and potentially send an email to us or watch out for hints.

[Note: I had a very busy weekend, including some mental health care which took me offline completely for 4 days, so have not reformatted the puzzles for this week yet or made the second “Smashing the Sudoku” video either. Amazingly, those busy weekends did not include full completion of the USPC or any participation in the MIT Mystery Hunt so things must be pretty serious for me right now. Reflecting on some of the comments from my post last Thursday, I do not want this site to go completely dark during my sabbatical year, but it may be less predictable when content gets added until we have our other puzzlemasters able to do web tasks more. That said, I also don’t think we need to release more free web puzzles without a new platform that can really grow our audience. Our planning for 2023+ has kicked off in a new GMPuzzles Discord channel that we will open up to authors/top fans soon.]

[This is a repost from our archives with new notes at the top: This Tight Fit Sudoku (original post linked) goes to eleven! While most Tight Fit sudoku use the range of 1-9, these larger grids — in this case one that has already filled all the “big cells” and only has Tight Fit cells left — can stretch your mind and your notation in interesting ways.]

PDF

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

Theme: The patterned digits in this Tight Fit Sudoku set up an interesting logical solve.

Rules: Standard Tight Fit Sudoku rules. Range is 1-11.

Estimated Difficulty*: 3 stars

Time Standards (highlight to view): Grandmaster = 3:45, Master = 7:30, Expert = 15:00

Solution: PDF and solving video.

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 our beginner-friendly collection Intro to GMPuzzles by Serkan Yürekli and in The Art of Sudoku 2.

[This is a repost from our archives with new notes at the top: The final Nurikabe (original post) of week two was one of our “best of” puzzles in our launch year 2013, with an interesting visual clock theme and again a different kind of use of wide open white spaces for that unexpected number (if it was going to be anything, it had to be a 13! There might come a time you might need a clock that can point at that).]

PDF

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

Theme: Nurikabe Time; don’t wait for the 13th hour to figure out where all the clock islands go.

Rules: Standard Nurikabe rules.

Estimated Difficulty*: 3 stars

Time Standards (highlight to view): Grandmaster = 2:00, Master = 5:00, Expert = 10:00

Solution: PDF and solving video; advice on solving this puzzle has also been posted in “Ask Dr. Sudoku #2“.

Note: Follow this link for classic Nurikabe and this link for Nurikabe variations. If you are new to this puzzle type, here are our easiest Nurikabe puzzles to get started on. More Nurikabe puzzles can be in The Art of Puzzles, in our beginner-friendly book Logic Puzzles 101, and in the e-book Nurikabe by Ashish Kumar.