bakpao's puzzles

Here's a Rail Pool I wrote last night. The idea to try for a fully symmetric grid apart from an unused cell randomly popped in my head. The top right requires a small lookahead that I didn't manage to get rid of, other than that I think this came out really cool. Difficulty: 3/5 (rules from Puzzle Rules ) Draw a non-intersecting loop through the centers of all cells. Clues represent all the different lengths of the straight line segments that are at least partially contained within the region. Each number within a region must be represented by at least one line segment. Play on pzprxs https://pzprxs.vercel.app/p?railpool/11/11/zm23p2t1l3t4w23w4t3l1t2p23zn000660f0601g0c0u0cc00002111o0s0500k0703ggg800000000800000000000000000

I participated in the 24 Hour Puzzle Championship again! It took place right after WSPC, in Eger, Hungary. If you've not had a chance to take a look at the puzzles yet, they are available here . Definitely check them out! This was the 22nd edition of the event, and it was my third time participating. I ranked 23rd this time, down from 13th last year. At first glance that seems like a significant drop, but with some 100 more participants this year, many of which are typically stronger solvers than myself, I'm pretty content with my result. I'd say I would have done better if I had prepared more for the event (which I hadn't much, because of WSPC), but I think that holds true for almost everyone there.  As always, the event was fantastic and tons of fun. I especially loved doing it with this many more people. I hope we see many of them return for future editions. Unlike previous years, this year's edition came directly after a week of already exhausting WSPC solving, ...

WSPC and 24HPC 2025 have concluded! This post will recap only WSPC - 24HPC will be in a different post, probably in a few days after I finish post-solving the rounds.  This was my 4th year in a row participating in WSPC. I was on the A team for Sudoku and on the B team for Puzzles this year.  I finished in 29th unofficial in WSC (25th official, 1st NL and up from 54th unofficial last year) and 38th unofficial in WPC (2nd NL, same rank as last year).  Last year I wasn't happy with my WSC performance. This year I dedicated almost all of my preparation time ahead of the championship week to sudoku, and my performance felt better because of it. I still feel like I performed rather poorly in a couple of rounds, especially on day 1, so (as always...) there remains plenty of room to do better. Overall though, breaching the top 30 and securing the top spot in NL feels like a solid improvement over last year. Because my focus on WSC inevitably meant a lack of preparation for WPC t...

Last year, I was invited to write puzzles for the 2024 Serbian Puzzle Championships!  It was my first time writing for this tournament, and I was briefed a structure where there would be 5 sets of puzzles: 1x Classics, 1x Variants, 1x Novelties, 1x Miniatures, 1x Longer Classics. It was never really clear to me whether I was supposed to write an entire set by myself or provide some puzzles for each set, so I ended up going for the latter. It turned out my submissions would all be in a single round (my own). Had I known, I probably would have opted for a different structure or maybe a common theme, but I think it ended up working quite well. Sticking to the categories meant the set has a nice variety to it.   The tournament ultimately was postponed and didn't happen in 2024, but it finally took place at the end of last month.  This is why a few of the puzzles are still themed around the number 24.  I also believe it was a shared championships between Serbia and Croati...

Here's a random simple loop that I wrote yesterday and don't really have any other place for - as always, a good excuse to get some content on the blog. Difficulty - 3/5 (rules from Puzzle Rules ) Draw a non-intersecting loop through the centers of all empty cells. Solve on puzz.link https://puzz.link/p?simpleloop/16/16/1s000230000o21444301g0043gg860404og00e00201804026400

WSPC 2024 has concluded! I made the trip to Beijing, China to compete for the 3rd time in a row, this time on the B team in both events following my absence at the Dutch championships this year (to take part in 24HPC instead).  I finished in 54th unofficial in WSC (3rd NL and down from 38th unofficial last year) and 38th unofficial in WPC (3rd NL and up from 47th unofficial last year).  I cannot be happy with my WSC performance - I lost 175 points  alone  to puzzles where I forgot to resolve the last two cells. That means a bit of careful checking at the end of each round would have been enough to jump me to 34th place and 1st NL. Perhaps with some more preparation in the days leading up to WSC (where instead I was enjoying long, active days sightseeing around Beijing), some of the many broken puzzles could have been avoided too and who knows, my result might actually have been good. Oh well. There's always next year.  I am quite happy with my WPC performance t...

Another year, another contribution to the Indian Puzzle Championship! This marks my 4th year in a row contributing to this event. I contributed 5 puzzles this year, which can be found in this post,  along with some rejects and leftovers . Like last year this post only contains the puzzles I wrote for the contest. The full IPC set can be purchased for a small price which helps LMI cover the costs incurred to organize the live event and continue to organize them in the future.  The full set contains all puzzle rounds, full of high quality puzzles, as well as bonus content like the PR Playoff puzzles and a giant interconnected puzzle gift. If you are able to, do consider purchasing the set. More information available  here  (IPC) and  here  (ISC) . Rules are included in the Penpa links, otherwise please refer to  Puzzle Rules . #1 - Star Battle - Round 1 - 30/500 points - Solve on  Penpa Mostly going for a clean theme and a not too difficult solve pa...

I was writing a Wafusuma for a project I'm contributing to and while doing so got the idea to try this set-up. It's a little gimmicky and I didn't put too much effort into it (this was the first location I tried for the rectangles - I did have to tweak the values though) but I think it turned out cute enough to publish it. There's probably a mean counting puzzle hiding in a different version of this idea as well. Difficulty - 2.5/5 (rules from Puzzle Rules ) Divide the grid into regions of orthogonally connected cells. Two regions of the same size may not share an edge. Borders must separate two different regions. A number on a border indicates the total number of cells contained in the two regions it separates. Solve on puzz.link https://puzz.link/p?wafusuma/10/10/u78g.h.h78m69m7am99p.i.zo.i886m475zs.iab95la976u

After supplying a round to the  offline portion of this year's UK championships , I was also invited to author some puzzles for the online event. This took place a while back, but I never got around to uploading the puzzles - here they are! I supplied five puzzles this time, of which three are in the first round and the other two in the second.  Be sure to also check out the other puzzles here (round 1) and here (round 2) . The puzzles are all good fun! Rues are included in the penpa links for all the puzzles. Enjoy! Round 1 Puzzle 1 - Balance Loop - 26/470 points https://tinyurl.com/2xq37x8s I mostly went for a striking visual theme in this one. A consequence of the lay-out I chose was that the break-in was a bit hard to find - some solvers had trouble getting started. It should be mostly smooth sailing after finding the correct entry point.

Last week, the GAPP project in the CTC server reached its 1000th day. To celebrate, the authors (myself included) collaborated on a large shading mashup, which was very positively received by many of our solvers. Feel free to check out the puzzle here , if you are in the CTC discord. Since my 100 blog entries milestone was also coming up, and I never ended up writing a big puzzle when I reached 1000 puzzles authored, I decided to write another puzzle on the same grid we used for GAPP1K, with the same genres and (mostly the same) rules, but without the difficulty cap. I expected the puzzle to take longer to finish, but it seems I got into a groove, and here it is!  Overall I'm very happy with it - I managed to preserve symmetry in all grids except the Half Piece one (where it really wasn't working out no matter what I tried) and built in lots of cool interactions between the various genres.  This puzzle is a fair bit more difficult and narrow than the GAPP one, so if you want t...

PuzzleDuel added Choco Banana to its genre selection yesterday. Apparently it was also World Chocolate Day. Two fine excuses to doodle a little puzzle!  Also, the next blog entry will be #100. I never ended up writing a big puzzle when I reached 1000 puzzles authored a while back, so maybe this time around I'll find the time to write something 🤞. Difficulty: 2.5/5 (rules from Puzzle Rules ) Shade some cells so that all areas of orthogonally connected shaded cells are rectangular and all areas of orthogonally connected unshaded cells are not rectangular. A clue represents the size of its group of shaded/unshaded cells. Solve on puzz.link https://puzz.link/p?cbanana/10/10/k65p6i4n3o8x6o8n8i6p48k

A fairly simple proof of concept that I wrote last night, to see if this combination works well and is worth diving into more in the future. I think it does! Difficulty: 2.5/5 (Base Canal View and LITS rules from Puzzle Rules ) Shade one tetromino of cells in each region so that all shaded cells form one orthogonally connected area and no 2x2 region is entirely shaded. Two tetrominoes of the same shape may not touch orthogonally, counting rotations and reflections as the same. Clues cannot be shaded, and represent the number of shaded cells connected in a straight line horizontally or vertically to the clue. Solve on Penpa https://tinyurl.com/2hcy2l5u

I went to participate in the 24 hour puzzle championship in Budapest again last weekend!  This was the 21st edition of the event, and it was my second time participating after my debut last year, in which I ranked 18th. This time I ranked 13th , so a solid improvement! Looking at the attendee list before the event, I thought my best possible result would be 12th, but also felt like I should be getting at least 14th. So, just like in 2023's WPC, I finished exactly where I predicted ahead of the event. Ironically, I didn't receive points for two puzzles that I solved fine, but only noticed it after the event was concluded - had I gotten them, I would have jumped to 12th place... :suseyes: Like last year, the event was tons of fun and a fantastic experience. I wasn't sure for a long while whether I would attend, as the tournament coincided with the Dutch championships. Since I intend to participate in WSPC later this year and our championships serve as the selection process f...

All the way back in October 2022, at WSPC in Krakow, Murat and I had the idea to organise an online contest with a special theme, meant to make solvers do a double take while solving: All puzzles were to be doppelgangers, or puzzles with a similar twist (such as expanding the grid without altering the clues, or inversing clues, like the puzzles below).  Besides the very strict theming, all the puzzles also needed to be fit for a contest and span a suitable difficulty range. Ultimately this lead to many failed attempts and many many hours spent on trying to get pairs of puzzles right. We managed to get to 12 finished puzzles for the contest before we lost the motivation to spend more time on it. We've been sitting on the puzzles ever since, waiting for inspiration to strike again one day, but unfortunately it never did and recently we decided to therefore abandon the project. A shame, but the positive is I get to showcase some of the puzzles I wrote for it here instead.  Revisi...

I was invited to write puzzles for the UKPA Open this year! The structure of this tournament was such that each author wrote an entire puzzle round by themselves, something I'd never done before. Lots of opportunities to go for fun theming, which shows throughout all the rounds (see the IBs here ).  I went for a round with 10 puzzles, divided into sets of two. A classic and a variant of the same genre, in each of the categories Loop, Shading, Region Division, Number Placement and Object Placement. I named the round "Something's Off!" in my head, a nod to each variant putting a twist on the given information somehow (with the slight exception of the Maxi Loop variant).  My round was the first of the day, and mostly leaned towards the easier side, with a couple of harder puzzles thrown in the mix. Rules are included in the penpa links for all puzzles. Puzzle 1 - Tapa - 16/383 points http://tinyurl.com/ysfobg6d A simple puzzle themed around only 2 and 4 clues, intended t...