I wanted to start this week by reintroducing this site for readers who may be visiting for the first time after reading a TIME magazine feature on the US Puzzle Team this week. Grandmaster Puzzles is the home to a range of logic puzzle types that may be familiar to you or completely new. I recommended that you start with the familiar, like Sudoku, and then move onto the new; every puzzle has a link to some rules and history that should help you get started. The puzzles get harder throughout the week so starting with the Monday/Tuesday tagged puzzles is a good way to sample the site too.

This is the last week in my 10-week “introduction” phase as I showcase puzzles in the last remaining style for The Art of Puzzles (Fillomino) and also bring you another view of sudoku from my past. While I intended this week to be the end of the first contest period at Grandmaster Puzzles too, with the indicated number of entries each getting a signed copy of one of our books (some spots remain), I am considering leaving the contest open until even more submissions have come in.

As we reach the end of the beginning, maybe it is time to reminisce a bit. Grandmaster Puzzles was a dream born in 2007 at the 2nd World Sudoku Championship to have a domestic source of quality logic puzzles. US magazines then primarily used, as today, computer-generated puzzles and mostly seemed to know that sudoku exists but nothing else. I knew something better could be made, and I suspected there were puzzle authors out there hungry for a place to submit their creations instead of just putting them up for free on the web. While it has taken some time to get off the ground, as other puzzle writing tasks and real-life have crowded out starting a puzzle publishing company, the pieces are clearly coming into place now. Having sampled some of the really excellent puzzle submissions I’ve been getting for The Art of Puzzles recently, I know that this dream will soon be accomplished. All that remains is to grow the audience of puzzle lovers aware of how amazing hand-crafted puzzles can be!

– Dr. S

Eighth in a series with puzzle solving tips. This time with advice on battleships puzzles, particularly missing clues and subs.

Solving Battleships is an odd experience for me. I think I want to enjoy them, but I’m not sure I ever really do very much. See, they were the first logic puzzle type I ever grew to love. But that means they also became the first logic puzzle type to bore me, and I’ve now been in the “bore me” stage for over half my life. And there is so much sameness in the Battleships you can find in the world right now. ~99% are randomly generated, ~99% give all of the outside clues which limits the challenge, ~99% solve by placing the largest ship(s) in the only possible spots and being good at bookkeeping of seas afterwards. As a member of the puzzling 1%, I am looking for something more. This week I tried to vary the formula a bit to make some more interesting — or at least different — puzzles.

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So last week was a week at sea for the solvers with Battleships and Battleship Sudoku. It was also my first week at SEA(ttle). And while it already feels like home I have a lot of apartment set-up to do still, and a growing pile of work as I take time to buy and build furniture.

My most observant solvers may have noticed I’ve been following particular genres in YRBGW order so far with my puzzle styles. If you don’t know what I mean, search the website a bit more. But I hate being predictable. I wrote a championship “Trophy” sudoku puzzle once with a first row ?2345678?. My occasional partner in puzzle-solving crime, Wei-Hwa Huang, saw that pattern and thought it was as likely that I would do 923456781 in a competition as 123456789 just to be sneaky. This week, I’ve decided I’ll just flip a coin to determine what I’ll post of the remaining options so you can’t possibly know better than 50:50 what puzzle type is coming. Or maybe that last sentence is a lie. Or maybe every other sentence in this paragraph is a lie. In all honesty, there are no hidden puzzles in this paragraph. But there are two more puzzle styles to come this week: a familiar sudoku style from me and Wei-Hwa, and whichever of “heads” or “tails” wins the coin toss today.

This week I’m going to start hiding the solving times behind a spoiler tag. I don’t know how choosing to see these times before starting will affect your solving, but I’d welcome a discussion on how times, or “points” on a competitive test, change your solving style. Does this differ when you have hand-crafted puzzles with a particular time goal versus, say, a generated croco-puzzle with a particular time standard set from other solvers?

There is no Doctor’s Note this week.

Seventh in a series with puzzle solving tips. This time with advice on exploring unusual puzzle geometries such as the Saturday Sudo-Kurve.

When you’ve solved enough 3d Sudoku or Sudo-Kurve puzzles or other unique geometries (as in Sudoku Masterpieces), you’ve probably recognized there are sometimes cells or sets of cells that are much more constrained than others in the construction. This Sudo-Kurve grid, which I used in Sudoku Cup 3 and only one other time since, has some secrets to observe before getting too deep into any puzzle.

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Sixth in a series with puzzle solving tips. This time with advice on both solving and constructing skyscrapers puzzles.

I’ve gotten a lot of requests for tips on how to construct puzzles. I don’t offer many online as I have a monthly column in GAMES magazine that covers this and I don’t like competing with myself for less money. But Mike Selinker and I have improved on that content recently in turning our columns into a book, Puzzlecraft: The Ultimate Guide on How to Construct Every Kind of Puzzle. Please check it out.

This week, I thought I would give some insights into how I made this puzzle. Since I often construct a puzzle by thinking in the same way that I would solve the puzzle, the images below will show you both how I made the grid (and when I needed to use certain clues) and also how solvers likely completed the grid (and when they needed to use certain clues).

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No real news this week. I’m moving away from San Francisco, so this week and next will be pretty brief Doctor’s Note-wise.

This coming week contains Tapa and Sudo-Kurve puzzles. As I’ve never posted a *classic* Tapa puzzle despite writing several, I needed to make a new example worthy for posting tomorrow on the Rules page. This example (about Wednesday difficulty) is a bonus puzzle for today, and there will be three more Tapa puzzles throughout the week.

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: Quadrants

Rules: Shade some squares black to create a single connected wall. Numbers in a cell indicate the length of consecutive shaded blocks in the neighboring cells. If there is more than one number in a cell, then there must be at least one white (unshaded) cell between the black cell groups. Cells with numbers cannot be shaded, and the shaded cells cannot form a 2×2 square anywhere in the grid.

Answer String: Enter the length of shaded segments, from left to right, in each of the indicated rows. Separate each row’s entry from the next with a comma.

Time Standard: Tapa Grandmaster = 1:00, Master = 2:00, Expert = 4:00

Solution: PDF

Fifth in a series with puzzle solving tips. This time, with some advice on global constraints that arise in loop puzzles.

Some of you have asked why I don’t put “general tips” up before I post any puzzles. I find that learning how to solve puzzles is more interesting than reading how to do every single step. I won’t post a list of the top 20 Slitherlink patterns you should memorize, for example, on the rules and info page. Most of you would probably get more enjoyment figuring those out for yourself. But, after you’ve solved a challenge, I do like highlighting some of the things as constructor I tried to include, perhaps as a lesson for the future. This is what I will do this week with parity constraints for the Friday Masyu.

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We’re now halfway through what I’ve been calling the “introduction” phase of Grandmaster Puzzles, in which I introduce the majority of the genres I’ll be including in my next few books, both as author and as editor. After the “introduction” phase, there will be puzzles by some other talented puzzle constructors here. And I hope to have over half of the puzzles in The Art of Puzzles written by others, maybe even you. I’ll be sending a detailed contributor email out by the end of the week so if you haven’t contacted me yet with interest in writing puzzles for these projects, now is the time to do so.

After the discussion last week, I’ve decided to change my reported time standards a bit. First, “Grandmaster” will be introduced and will be equivalent to about where Master was set before, timed close to my best test-solver and equivalent to where I expect someone in the top 10 in the world to be. Master will now be set around the median of my group of solvers, which will be about where a 10th place USPC finisher will be or about top 100 in the world. In some sense these two times will inform on the mean and s.d. of the puzzle, and can highlight the Aha nature versus speed nature of particular solves as I have a few where one solver blazes through but the average solve takes much longer. Expert will be set at 2x the new Master time, which will often be close to the old 3x of GM but is hopefully more stable as it is using many more solvers’ data. There will no longer be a Novice time. It has not been a very useful measure at all, and I think has encouraged more disappointment than cheer from people trying to target it.

Next week will be “Think Outside the Box” week, with two puzzle styles where the clues are outside the grid. That should be a pretty easy Puzzle and Sudoku pair to identify, and I hope you enjoy the set of challenges I’ve lined up.

Best,
Dr. S.

Fourth in a series with puzzle solving tips. This time, basic steps to get through Cave puzzles.

While I’ve already written a good description of solving Cave (Corral) puzzles for the USPC, I’ve never drawn up some of the steps for more visual solvers. This week I hope to fix that by highlighting one of the more fundamental logic steps behind these puzzles.

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Still recovering from my trip to Boston so this week’s note will be brief. I hope you enjoyed the Arrow Sudoku and Cave Puzzles. This coming week will bring the first of the loop puzzle genres, Masyu, and Consecutive Sudoku, another of my favorite sudoku variants from the past, in this case from explorations in Mutant Sudoku.

As the topic for this week, I want to know what you think of the times given with the puzzle each day. For the competitive puzzlers, do you like seeing these times? Is the master time a bit too hard to reach? Would a slightly easier standard give a better target? For the recreational puzzlers, does seeing a time change how you approach the puzzle to care more about the clock than otherwise? Would you like an option to keep them hidden instead?

I am considering adding a self-reporting of times to the solve box once there is a finishers page for each puzzle. It is not a high priority at the moment as I view the times as a guideline to set an expectation for the puzzle, and not yet that my site is a “competitive puzzle site” like some others that record solving histories and such. But I welcome your input on any changes you might like me to think about going forward since I do have several excellent testers that have been giving me good data every day.

Cheers,
Dr. S