Puzzle No. 500 – 9 Shady Masterminds [Special] [Marathon]

I thought quite a bit about what I wanted for my 500th puzzle here. There was a stage when I thought I’d just ignore the milestone and post something normal. Then I got a bit of an idea of a simple theme which might still give out a nice solve path with different logical deductions combining.

The puzzle that resulted from this idea is pretty narrow and quite difficult, according to my and Swaroop‘s test solving experiences. Still, I think its ended up being quite varied in the thinking required and I like how it turned out.

Unlike my usual approach of posting a single image, for this puzzle I am attaching a PDF instead. This PDF has 4 pages. The first page contains the puzzle. The 2nd and 3rd pages contain the rules (The length is just because there are 9 different puzzles to cover, but most of them are familiar and should just be a quick read-through). There are two newer puzzle types, and one variant which I couldn’t immediately find an example for, so I have added 6×6 examples for these three rule-sets. The remaining are all classics, so I’ve just linked to the respective page where I got the rules from, and you can visit these links if you want an example. If you are new here and haven’t seen those sites before, I suggest visiting them anyway for more great puzzles.

Here’s the PDF:

Please let me know in the comments or by mail (prasanna16391@gmail.com) if you have any queries regarding the rules or any other issues.

Puzzle No. 469, 470 : Regional Tapa, Regional Snake

I took a week long break from puzzle construction, which was a little “forced”. Now I’m starting again from tomorrow,  and I want to start fresh, so discarding all my “reserve” puzzles and starting new on everything, as I like to do after a break.

The Regional Tapa isn’t that difficult but the Snake is.

Rules –

P469 – Rules of Tapa. Additionally, a clue also indicates the length of shaded cell groups in its region (in the exact configuration as the clue). Some regions may not have clues and have no restrictions. A “?” can stand for any number, but the number(s) needs to be constant for the clue cell as well as the region it is in.

P470 – Find a snake in the grid whose body consists of horizontal and vertical segments. The snake’s body never touches itself, not even diagonally. The head and tail of the snake are not given. Numbers in each of the regions surrounded by thick lines denote the number of cells occupied by the snake in that region.

Enjoy!

P469

P470

Puzzle No. 454, 455 : Odd-Even Tapa

Few more puzzles that were part of WPC practice.

Rules – Follow regular Tapa rules. Instead of normal numerical clues, all odd digits are replaced by “O” and all even digits are replaced by “E”. (E cannot be 0)

Rated – Around the Easy/Medium mark for both.

Enjoy!

P454

P455

Puzzle No. 444-447 : Puzzles from the Visa Application office

In addition to my usual puzzle related activities, I have been managing Team India’s visa application submissions. This has been quite a tough process. As part of the process, I have to stand in queue outside the office for 4 and a half hours, and then sit inside for about an hour more. The puzzles below were part of 9 I wrote when sitting in the office. I was obviously exhausted, and this was more of a “oh, I found a pen and paper, lemme just have a little fun to pass the time” kind of activity. Also, with a pen, I couldn’t erase stuff which makes construction infinitely harder, at least for me. So out of the 9, only 2 ended up working when I reproduced them on the computer. 2 others had easy fixes. The other 5 will have to be discarded as I can’t see what I can do to make them work. This hopefully makes up for my inactivity on this as well as next Thursday. Other than the league post on Tuesday, my next post will be a week after this.

Of the 4 puzzles that made the cut, 3 are Tapa related. This is fitting, as the TVC and CTC are nearing their end. I feel fairly certain of a top 10 finish in CTC, and hopefully somewhere thereabouts in TVC too. Generally happy with how I’ve done this year. The 3 puzzles below have a nice mix of a Classic Tapa, a variant that appeared this year, and a variant from the past. The 4th puzzle is a Shakashaka, which is nothing special.

In other news, the “Around the world in 80 Puzzles” Instruction booklet is out! As announced on this blog before, one of the 4 sets is written by me. I’d like to thank Amit Sowani, for test solving each puzzle and providing some good inputs along the way. I thank Ravi Kumar too, for coming up with the name Indian Intrigue which I liked the most out of the possible names. It was a pleasure working with Zoltan Nemeth and the other Hungarian team members too.

Anyway, puzzles!

P444 : Tapa. Rules for Tapa.

Rated : Medium (could be hard).

P445 : Twopa. If both grids are considered together using the following rule, they will each have a unique solution. In each solution, every clue must behave at least a little bit differently. This means, in a multi-digit clue, some of the digits can have the same behavior, but not all.

Rated : Medium.

P446 : Tapa Trimino. Follow regular Tapa rules (above). Additionally, the wall should only be made up of “L” shaped triminoes without overlapping.

Rated : Hard.

P447 : Shakashaka. Rules for Shakashaka.

Rated : Easy.

P444

P445

P446

P447

Puzzle No. 440, 441 : Tapa [Touch and Go]

I’ll just quickly link to a few of my contributions to the recent Czech Team Sudoku and Puzzle Championships.

1. I co-authored a Sudoku team round with Tom Collyer. The round has easy classics, that give some digits which need to be transferred to harder variants. The Weighted Killer, the Outside or Skyscraper, the Rossini and the Battenburg are all written by me. They are all uniquely solvable, without the transferred digits, but obviously, the transferring makes them easier. This Sudoku round is the 6th round, and can be found in PDF numbers 28 and 29 in the Sunday tab of the above link.

2. I wrote two team puzzles, one being an interconnected wall puzzle, a combination of LITS, Nurikabe and Tapa. This puzzle has two versions. The original version included determining where the part-grids go as well as solving them. Based on testing times, I decided to make it easier and gave the positioning of the 9 grids at the start itself. The detailed wall rules and the actual competition puzzle can be found on the Sunday tab of the above link, it is the 6th Puzzle round, which is PDF numbers 35 and 36. There are English rules there too. The original version of the puzzle, with just the layout given and some added logic required in placing the part-grids correctly, is given below.

OriginalWall

3. The second team puzzle was a Loop puzzle. It is a combination of 4 loop types, a Masyu, a Yajilin, a Simple Loop and a Country Road. There’s an added rule that there are certain shaded cell positions given where the loop segment behaviour is exactly the same for all 4 grids. This can be found on the Saturday tab, it is the 2nd puzzle round, PDF numbers 16, 17 and 18.

To today’s puzzles now. I came up with this variant today, and liked it enough to use it in two puzzles. I didn’t really check if the variant exists already, but I can’t remember solving one with these rules.

Rules – Follow regular Tapa Rules. Additionally, no dead-end can ever be a part of a checkerboard pattern. A dead-end is a shaded cell with just one orthogonally adjacent shaded cell, and a checkerboard pattern is a 2×2 area of alternating shaded and unshaded squares. Note : The clue cells are also considered as unshaded cells for the checkerboard pattern.

Rated – Medium (the first one’s on the easy side and the next one’s harder)

Enjoy!

P440

P441

Puzzle No. 436, 437 : Fillomino, Tapa

As promised, here’s 2 puzzles to make up for missing out on Sunday. The Fillomino’s just something I made to explore the middle pattern. The Tapa is one of those that was meant for elsewhere, but the theme was pretty nice so I decided to move it here. Its got my favorite (symmetric clues have same sums) theme, while all symmetric clues are still different. Its also got a decent un-clued space in the middle.

P436 –

Rules for Fillomino.

Rated – Medium (easy side).

P437 –

Rules for Tapa.

Rated – Easy.

Enjoy!

P436

P437

Puzzle No. 431 : Tapa

This one’s a bit gimmick-y. I tried not to make it too obvious, and keep it a little interesting. Still pretty easy though. Just wanted to have a try at something. This mostly wouldn’t have met the quality levels of the Tapas on the Classic Tapa Contest going on right now (Self Deprecation as an advertisement for something else, how awesome am I?!). Oh and, seeing as my schedule dictates that my next post be on Sunday, I’ll also note that Tapa Variations Contest XIV is this weekend. Yay!

Aaanyway,

Rules for Tapa.

Rated – Easy.

Enjoy!

P431

Puzzle No. 425 : Tapa [Diagonal Neighbors]

I thought I’ll add another practice puzzle for the Tapa Variations Contest coming up this weekend. This is a variant I thought up and there’s 2 other instances on this blog that Serkan has linked to in the forum. This particular puzzle isn’t especially tricky but uses the Diagonal rule nicely I think.