Puzzlers Club is a Discord-based community of puzzle lovers. They have contributed for 24-Hour Puzzle Championship in 2018 and 2019. This is the first contest organized collectively as a group by this team. There will be two tests - this is Part 1. Part 2 will come next month, in August 2019, as a separate contest.

This test will have a mix of easy, medium and hard puzzles, and will be included as a rated test for LMI Puzzle ratings.

Instructions and more details - http://logicmastersindia.com/2019/07P/

I'm back, and this time with a train of authors! Some of us return to write to LMI again, some of us are brand new, but all of us want to showcase our styles and creations. Some genres are very common, some are thematic twists of them, and some make their first appearances here, having never existed before. Some puzzles prove to be easy points, while others will prove to be a tough challenge. What's in common is that we are Puzzlers Club, and we hope you'll enjoy the test! If you have any questions, feel free to ask.

Both antisymmetric instructions should really say ‘rotationally symmetric’ instead of just ‘symmetric’.

Oops, right. The first draft of the IB had "rotationally symmetric"; I then removed it because people might ask, with respect to what? On retrospect it would have still been better than simply "symmetric".

I'm left wondering why the answer key changed between 12 and 13/14.

Thanks for a great test! Haisu is the best new puzzle type I've seen this year - it seems to have a lot of possibility and the ones in the test are really good.

Favorite Puzzles:

01 Masyu
06 Total Masyu
11 Haisu
14 Statue Islands
21 Poset Futoshiki

Thanks again, and I'm excited for Part 2!

I think I did pretty well in this test, considering that I'm not very comfortable with Masyu. I especially loved the Fillomino (Checkered). Kudos to Rob for that!

Timjamiller: Oh whoops, that was a mistake. The initial answer key didn't repeat letters, but we changed it to repeat letters because of some possible issues (e.g. an U pinching another shape: when is the U counted, before or after or both?). But apparently I only changed 12 and didn't change 13-14. I greatly apologize for this oversight. We'll mark all answers for 12-14 that only put one letter per shape to be correct as well.

Thanks for the test. I had a lot of fun.
It seems all the grids (at least the ones I managed) had neat paths!
Definitely a lot of a-ha moments and that sense of satisfaction when each grid is solved.

I got bogged down by the Checkered Fillomino, Anti-symmetric Tapa and the Poset Futoshiki.
High-pointers (and very nice flows to them!) but meant no time left for everything else.
Looking forward to Part 2.

Congratulations to EKBM, WA1729, and panista for the podium finish, as well as to Para and S_Aoki for also completing the whole test! And thank you for all participants for taking part in this contest, and all the feedback. Also, to WA1729: TheGreatEscaper appreciated your love of Haisu. I also hope it becomes a staple genre in logic puzzles.

As the contest progressed, we noticed a few issues. One was listed above: we accidentally put the old version of the answer key for 13-14 (Statue Islands), leading to many confusion. We greatly apologize for the mistake, and the time that might have spent double-checking and such. We also noticed that a few puzzles ended up not valued that fairly; I believe 6 (Total Masyu) and 19 (Nurikabe) proved to be more difficult than they appeared. (I wish the usual feedback page was up; people seemed to be much more willing to give feedback through it, and it would have been great to see if people thought the scores were okay or not.)

There is Solution Booklet that should be uploaded soon; it has hints for some selected puzzles, and we're also happy to help you answering questions on how to get past a difficult step. Do try all the puzzles even after the contest is over; they are all good!

Some trivia about the puzzles:
- 6 (Total Masyu) was originally a Uniqueness Triplet Total Masyu. You have three grids; one has a unique solution, one has multiple, and one has none. Find which is which. The reason is that the puzzle as in the contest might be prone to uniqueness logic. We axed the Uniqueness Triplet part. (It was also originally 10x10 with an empty bottom half.)
- As explained in the IB, Haisu originally had a second kind of clues; a small number at the top-left of a region counts the number of times the path enters the region. It appeared in 24HPC 2019 without that kind of clues, but the IB there still had it; this is the first time Haisu is presented without reference to that kind of clues at all.
- ManyPinkHats had a third genre involving rotationally symmetric variants of an existing puzzle, but we cut it in exchange for expanding the other two genres. We'll see if there's any other rejects that are good enough to share!
- 16 (second Antisymmetric Tapa) was nerfed in the last few days before the contest went live. It is solvable without the R8C3 clue.
- 19 (Nurikabe) is meant to be solved with intuition. There is a logical argument, but it is very advanced.
- 21 (Poset Futoshiki) was feared to be too difficult to be included in the test. It seems that it ended up fine; nowhere near the list of least-solved puzzles.
- For my section personally, I had reasons for my selection of puzzles: Fillomino is my favorite genre, Poset Futoshiki is my invented variant that I'm most proud of (I considered putting Maximal Archipelago as well but didn't get it to work quickly enough), and the Nurikabe showcases a logical deduction that I derived a few months ago. I'm not sure if other people have their own motivations for their particular section (of why they picked those genres); that's for the others to answer.

Really, the history section explains pretty much all about the motivation. We formed our own group, Puzzlers Club, that is more puzzle-focused about 1.5 years ago. Then we wrote to 24HPC 2018 (Round 3, themed around the number 3), then 24HPC 2019 (three rounds: 7, 10, 11). Then I figured, why not write for LMI too? And since we want to introduce ourselves, I figured we could turn it into a theme, and so here we are.

Of course, we aren't done yet. There's still Part 2, because we have 14 interested authors and that's way too many for one contest. Expect another collection of high-quality puzzles next month! And even after that, it won't be the last; we'd be happy to write more for LMI and produce more interesting puzzles for people to solve.

Finally, if you are interested in joining us, you can e-mail at puzzlersclubsignups -at- gmail -dot- com. We're happy to have anyone that's interested in puzzles! We're a bit hesitant with being too open to the public, as it usually invites bots and spammers; as such, if you're interested in joining, please state that you hear about us from this test.

See you in Part 2!

Congratulations to Swaroop, Kishore and Harmeet for finishing in the Top 3 from India!

Thanks to all the authors and test-solvers for coming up with this wonderful set of puzzles.

The Solution booklet please !

Solution Booklet: http://logicmastersindia.com/lmitests/dl.asp?attachmentid=789