[This is a repost from our archives with new notes at the top (original post here): Making images of smiley faces in puzzle form is one way I try to make the world at least 1% happier. This Wednesday Masyu has a couple less common lookahead steps but should continue to be a good introduction to the genre for those without much prior familiarity (this was a bigger gap in 2013 when the puzzle was written than in 2023).]

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: Smiley Face – our first (but probably not last) use of this theme here.

Rules: Standard Masyu rules.

Estimated Difficulty*: 1.5 stars

Time Standards (highlight to view): Grandmaster = 0:40, Master = 1:15, Expert = 2:30

Solution: PDF

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

Several members of the GMPuzzles family are from Turkey, and our thoughts go out to them and to others from Turkey and Syria who may have been affected or may know those affected by the recent earthquakes on the Turkish/Syrian border.

GMPuzzles will be donating all proceeds from book sales for the next ten days to relief efforts like those of the Turkish Red Crescent; we will also match any donations that come in via PayPal over the same period (see Tip Jar in left menu). As an advance against those amounts, we’ve given $1,000 to https://ahbap.org/disasters-turkey.

Update 12 Feb 2023: Serkan has constructed a puzzle to help raise awareness and funding for those impacted by the earthquake. We’ve put together this simplified PDF to be able to play along with the puzzle.

The puzzle was also featured on Cracking the Cryptic:

with this link to play the puzzle online.

[This is a repost from our archives with new notes at the top (original post here): Consecutive Sudoku is one of the most basic variations of Sudoku to uses properties of the numbers to help place sets of digits into the grid. Wei-Hwa Huang and I included it in Mutant Sudoku with several artistic themes, despite the challenges that the “anti”-rule forces into puzzles for having no consecutive digits when bars are not present. In future years, GMPuzzles prioritized Consecutive Pairs Sudoku which only uses the positive information of known pairs for cleaner themes and easier solving. But as we look back on our past, this week will show examples of me pushing the limits of a style with two kinds of constraints, positive and negative, across every pair of cells.

PDF

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

Theme: Hashtag Fun? A consecutive sudoku with a large # in the middle.

Rules: Standard Consecutive Sudoku rules.

Estimated Difficulty*: 2 stars

Time Standards (highlight to view): Grandmaster = 2:00, Master = 3:00, Expert = 6:00

Solution: PDF

Note: Follow this link for other Consecutive Sudoku. If you are new to this puzzle type, here are our easiest Consecutive Sudoku to get started on.

[This is a repost from our archives with new notes at the top (original post here): Our first Loop/Path puzzle genre on the site was Masyu, a style from Nikoli that focuses on white and black clue elements on a big grid, sharing some visual inspiration from Go. The distinct rules of going straight through and turning at the “pearls” leads to different kinds of logic as seen in this “25th” puzzle from over a decade ago.]

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: Our 25th prescription! Enjoy this easy Masyu puzzle.

Rules: Standard Masyu rules.

Estimated Difficulty*: 1 star

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

Solution: PDF

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

See these earlier posts 1, 2, and 3 for the other Microsoft Puzzle Hunt challenges

Puzzle PDF

Author/Opus: This is the 433rd puzzle from Thomas Snyder, aka Dr. Sudoku.

Hints:
1. How do I get started? Pbafvqre gur fvatyr pryy ahzorerq fdhnerf dhvgr pnershyyl gb uryc svther bhg jung xvaq bs chmmyr guvf vf.
2. How do I solve this? Guvf vf n UVQNGB chmmyr jvgu ahzrevpny pbafgenvagf nf va n GbzGbz/Pnyphqbxh npebff pryyf. Sbe rknzcyr, gur 8÷ pntr pbagnvaf n 3 naq 24 (nf 24/3 = 8).
3. How do I get a final answer? Gur sbhe ? fdhnerf pbagnva gur inyhrf 46, 73, 85, naq 97 va fbzr beqre. Ohg gurfr inyhrf jba’g or nf vzcbegnag gb svavfu gur chmmyr nf gur cngu gb trg guebhtu gurz.

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.

We’ve just published our fourth episode of Smashing the Sudoku as we look back at our first puzzles from ten years ago and try to bring back memories of these constructions from our first 60+1 puzzles:

In a few minutes we will also have our fourth Microsoft Puzzle Hunt bonus puzzle, which we hope you all enjoy.

[This is a repost from our archives with new notes at the top (original post here): The third arrow Sudoku puzzle in our GMPuzzles introduction series contains a lot of “split” arrows with multiple paths all equaling the same total sum. Steady progress going arrow by arrow around the grid should let you eventually find the unique answer.]

PDF

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

Theme: Multi-arrow Challenge! Also, there is a 1-9 “digit pangram” in the nine givens.

Rules: Standard Arrow Sudoku rules.

Estimated Difficulty*: 4 stars

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

Solution: PDF and solving video.

Note: Follow this link for more Arrow Sudoku. If you are new to this puzzle type, here are our easiest Arrow Sudoku to get started on. More Arrow Sudoku puzzles can be found in The Art of Sudoku 2 and Masterpiece Sudoku Mix 3.

[This is a repost from our archives with new notes at the top (original post here): The last Cave puzzle in our starting week has some interesting border clues that should set up for a different kind of solving path if you are paying attention.

PDF

or solve online (using our beta test of Penpa-Edit tools; use tab to shift between shading mode and the linex mode where left click+drag draws lines and right click marks X’s)

Theme: An Almost Perfect 10? The border of this Cave puzzle is almost completely uniform.

Rules: Standard Cave rules.

Estimated Difficulty*: 3 stars

Time Standards (highlight to view): Grandmaster = 3:15, Master = 6:00, Expert = 12:00

Solution: PDF and solving video.

Note: Follow this link for classic Caves and this link for Cave variations. If you are new to this puzzle type, here are our easiest Cave Puzzles to get started on. More Cave puzzles can be found in Roger Barkan’s Colossal Cave Collection, in The Art of Puzzles, 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): The best Arrow Sudoku puzzles usually have a few fully constrained arrow clues at the start to be the “seeds” for the logical path to the solution. Can you find where these seeds are in this “Flower Blossom” theme?

PDF

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

Theme: Flower Blossom – The cells with arrows look a little like the petals of a flower and are heavily involved in the solving path.

Rules: Standard Arrow Sudoku rules.

Estimated Difficulty*: 2.5 stars

Time Standards (highlight to view): Grandmaster = 3:45, Master = 5:30, Expert = 11:00

Solution: PDF

Note: Follow this link for more Arrow Sudoku. If you are new to this puzzle type, here are our easiest Arrow Sudoku to get started on. More Arrow Sudoku puzzles can be found in The Art of Sudoku 2 and Masterpiece Sudoku Mix 3.

After a tough January with assorted things like a power outage impacting our ability to compete on the United States Puzzle Championship, and many more events around my science work leading to a mental health break, we’re back on track for most of our 2023 projects. For Grandmaster Puzzles, we’ve now completed our recent “Best Of” series is now finished and we just released our third edition of “Smashing the Sudoku” to go along with our original 60+1 puzzle set.

Coming in the future will be some invites to puzzle contributors and top fans for our Discord channel where we are brainstorming what is next for the site (in 2023 and out to 2033 in a ten year plan), a new approach to web content, and more info on puzzle championships that GMPuzzles will be involved in.