Community Building

This is a bit of a ‘random thoughts’ kinda post. But before I go on, I want to share that my parents got me this T-shirt and I love it:

Anyway, the main reason for this post is, I’ve been thinking about the difference between casual puzzle solving and competitive puzzle solving. Soon I’ll be starting the 2023 editions of Sudoku Mahabharat and Puzzle Ramayan, and the WPF will start the 2023 editions of the Sudoku GP and Puzzle GP. There are competitions galore online and maybe some offline too as we start another season leading up to the World Championships. *Edit*: I shouldn’t mention all this without mentioning the lovely beginner-friendly contest this weekend on LMI, PANFOPCWHTTAPA 3. The first two editions were great for newer solvers looking to learn new puzzle genres and get into competitive solving for the first time. Check it out!

This process, largely, ignoring small mishaps and challenges here and there, has been carried out quite smoothly in recent years (in another discussion it may be worth actually appreciating what we are able to do as a community year on year with little to no monetary benefit and a heavy lack of personnel in some cases) and I have confidence that that will continue.

However, this post is for discussing other things we can do, to keep the casual puzzlers component of the community involved through the year to a similar extent. I’m very interested in exploring this side of things more. Over recent years I have been trying to capture people in different ways. One big way is trying to expand our author pool for SM and PR and give new and young authors a chance and platform. Puzzle construction doesn’t involve the same pressures of competitive solving and is probably more accessible in that sense for those who are interested in the hobby to keep in touch with it meaningfully.

Another way is to hold more casual mini-events as part of our National Championships. During the offline Indian Sudoku Championship there was a simple team round I ran after the main competition while the organizers were checking, where groups of 3 got together to figure out the connection between some Sudokus and try to solve them together. Similarly, during the offline Indian puzzle Championship, I simply put together groups led by some prominent authors of our community, to teach people the processes involved in writing puzzles. The aim of these side events (other than giving the checkers time to put out the results) is to introduce a social component within the experience.

The last way, which I don’t see enough of (I may just be missing it) across the community and probably want to focus on more here, is to hold meetups regularly. Since India is a large country, we mostly plan meetups specifically for Mumbai, the city I live in. The first meetup I had in Mumbai, was basically just a two-person hangout where I helped another solver get through some tough Sudokus. This was many years ago, and since then, with that other solver’s help and others along the way, we built a regular functioning group with monthly meetups in the area.

After the obvious gap caused by Covid-19, we are now rebuilding this meetup culture. We have a stable venue and a consistent agenda comprising of:
1. Casually start solving some (hopefully) approachable Sudokus that vaguely escalate in difficulty while I float around helping where needed, but also get aided by the stronger solvers who attend these.

2. Introducing and teaching a new non-Sudoku puzzle type.

3. Having a team-solving round from some past competition, trying to group more established solvers with newer/casual ones.

The feedback I’ve got from the participants is overwhelmingly positive, and over the years its given some casual solvers a good way to stay connected. It also gives some of them more encouragement to participate in competitions, knowing that the social component carries forward even if they’re not necessarily contenders for the top positions.

The other, more unexpected positive I’ve seen is the variance in demographic. While most of India’s (and the world’s) top solvers are males around 25-35 years of age, the Sudoku meets I conduct have many regular female participants. I can’t help but feel there’s something there, for whatever reasons, with casual solving being more appealing to female puzzlers than competitive solving. I remember conducting a meet pre-covid where there were 22 participants and 20 were female! The demographic has leveled out more post covid, but it is still usually a good ratio.

These meets are pretty easy to conduct. Find a local cafe that allows for group meetups, use some selection of puzzles from an old LMI set or GP set or WSC/WPC set and just get together and interact while solving. It probably helps to have some solvers around who are more established and can help, but it is quite doable without that too.

I’d like to see more offline meetups in different places. I think it definitely benefits the community in ways that competitions do not and goes hand in hand nicely with the competitive part.

I’d also love to see other suggestions to tap into casual puzzle solving audiences and keep them engaged. There have been some good attempts, with Tawan’s quizzes and contests, the Puzzle GP’s experiment with a casual section, etc. which are good ideas to build on too.

I’ll end this post with photos from our most recent meet, where they surprised me with a cake and a small celebration at the end of the meet to commemorate my WPC performance. It was a fulfilling and heartwarming end to the meet and shows that we are building a pretty cool community with these meets.


Puzzle No. 511: Arrow + Between 1 & 9 Sudoku

I want to call the variant a lot of people now know as “Sandwich” by what it used to be called, including in past posts on this very blog. This is a puzzle I’d worked on a while back, for a speedsetting contest that I was too late to submit to.

In other news, the WPF Sudoku Grand Prix final results are here –

There could be a minor change or two since the round 8 results are still “preliminary” but I’m confident that my final placement won’t change. So I’m 6th! Considering I started the year targeting a top 10 finish, I’m pretty happy with this. I had a really strong finish in the last 2 rounds.

What else.. oh ya, I just wanted to note that this is the vague schedule I’ll be going for (every alternate day). I’ll branch out on topics as I go I think.

Rules –

Insert a digit from 1 to 9 into each cell so that no digit repeats in any row, column, or bold region.

Additionally, the number in a circle is the sum of the digits which are covered by its arrow. Digits may repeat along arrows.

Also, the clues outside the grid are the sum of the numbers that are between the digits 1 and 9 in that row or column.

Penpa link to solve: (You can tab with surface and Sudoku, the answer check is just for correct digits)

Puzzle No. 509: Triomino Sudoku [Daily League]

I’ve got wayyy too much to do these days, so I’ve pretty much stopped any regularity on this blog. I might make the rare post though, like this one. I was a little bored of work and had some time so quickly explored this variant that’s part of the Indian Sudoku Championship which will be held online on LMI in about 13.5 hours. This one is pretty difficult (as are all variants I randomly and quickly post here when bored), but has some nice steps to get started.

Remember that you can solve the puzzles from the League online on the Sudokucup Guest League page with a 24h delay (though I’m not yet sure if this one can be supported there, but take a leap of faith, maybe it will be!).

Rules – Place a digit from 1 to 6 into each empty cell or blacken the cell so that each digit appears exactly once in every row, column, and outlined 3×3 region along with three black(shaded) cells. Each black(shaded) cell should be part of an orthogonally connected group of three blackened(shaded) cells (a triomino). No two triominoes can share an edge.




Puzzle No. 506 & 507: Trio Sudoku, Anti-Diagonal Sudoku [Daily League]

The Trio Sudoku is actually last week’s puzzle. I’d posted it on facebook but hadn’t posted it here. Thats rectified now. Its not the usual Trio Sudoku, but I prefer this slight tweak because it gives more to work with overall.

Remember that you can solve the puzzles from the League online on the Sudokucup Guest League page with a 24h delay. The Anti-Diagonal is today’s offering and will be the one appearing tomorrow on the online solver.

Also, a new puzzle genre I thought of debuted on GM Puzzles this past week. Its called Balance Loop. Have a go at these!

Balance Loop 1.

Balance Loop 2.

Balance Loop 3.

Rules for 506 – Follow regular Sudoku rules. Additionally, Circles must contain only digits 1, 2 and 3. Small squares must contain only digits 4, 5 and 6. Diamonds must contain only digits 7, 8 and 9.

Rules for 507 – Follow regular Sudoku rules. Additionally, each marked diagonal must contain exactly three distinct digits.




Puzzle No. 505: Anti-Clone Sudoku [Daily League]

I’ve had enough of Saturdays where I forget its a Saturday. The days I remember are usually Tuesday, Thursday and Sunday, for no specific reason other than that I’m weird. So, I’ve switched Sunday with Rajesh Kumar for the Daily League and I’m hoping that means I remember to post regularly.

Remember that you can solve the puzzles from the League online on the Sudokucup Guest League page with a 24h delay.

Rules – Follow regular Sudoku rules. The digits at the same locations on each shaded area must sum to 10. Shaded areas cannot be rotated or reflected.



Puzzle No. 504: Search 9 Sudoku [Daily League]

I’m back to the league this week and I hope that I’ll be back regularly now. Anyway, Search 9 Sudoku for today.

Remember that you can solve the puzzles from the League online on the Sudokucup Guest League page with a 24h delay.

Rules – Follow regular Sudoku rules. Additionally, each arrow points to the 9 in the respective row or column. The number in the cell with the arrow is the distance from the cell to the 9 in this row or column.




Puzzle No. 503 – Diagonal Sudoku [Daily League]

I’m hoping for a bit of free time at the end of the year, I might put up a detailed post about… stuff, then. For now, Sudoku! This might be hard but don’t take my word for it.

Remember that you can solve the puzzles from the League online on the Sudokucup Guest League page with a 24h delay.

Rules – Follow regular Sudoku rules. Additionally, each marked diagonal must also contain all digits from 1~9.

P503 - Diagonal Sudoku

P503 – Diagonal Sudoku

Puzzle No. 501 & 502 – Killer Sudoku & Extra Region Sudoku [Daily League]

Now that I’ve posted my 500th puzzle, I am sharing the Sudoku I contributed to the Daily League last Saturday, along with the Sudoku I’m contributing for it today. I didn’t post the Killer last week on my blog because I wanted the space saved for the special puzzle.

Remember that you can solve the puzzles from the League online on the Sudokucup Guest League page with a 24h delay.

Common Rules – Follow regular Sudoku rules.

For Killer The number in the top-left corner of a dotted cage is equal to the sum of this cage’s digits. No digit can repeat within a cage.

For Extra Regions – Each group of nine grey cells must also contain the digits 1 to 9.



P501 – Killer Sudoku


P502 – Extra Region Sudoku

Some solving steps for Puzzle 499, a bit about LMI, and some other stuff

I am attaching a mini-walkthrough PDF for the Arrow Sudoku I posted for the league recently. Its a bit rushed, and only takes the solve through the more difficult deductions, but should be really helpful if you were stuck on that Arrow Sudoku or didn’t attempt it but want to know more about the variant in general. Here’s the PDF –


Now, a bit of a plug. Want more walkthroughs? We do much more detailed ones for LMI patrons. Also, I should say that, at least currently, supporting LMI would mean you are supporting my personal goals too (which is why I don’t have any such effort for this blog).

Also, I might have to disappoint any fans of milestone puzzles by saying that I currently don’t have anything planned. But you never know right? Maybe I think of something worthwhile in the next few days. If I don’t, then come Saturday I’ll just post a League Sudoku as my 500th and that’ll be that.

Soon I’ll be shifting residence, so I’m generally a bit more busy since I want to finish a bunch of things before I probably lose internet access for a week or two.