Puzzle #82: Yajilin

Happy New Years India

I know, I'm over 2 hours late, but they crossed into 2012 18 minutes after my last post.

Yajilin was the obvious choice for me for the number 1. It's a genre that never uses very high clue numbers in a small grid. It took some effort to get a good puzzle out of it that was also a bit challenging.I think it's representative of some of my earlier Yajilin puzzles, even though there's no nice symmetrical layout this time. It's still a good solve of medium-hard difficulty.

1. Yajilin

Colour some cells so that you can draw a closed loop through all remaining white cells. The numbers in the grid tell you how many coloured cells can be seen in the direction of the arrow. No coloured cells are allowed to share an edge.

Puzzle #81: Liar Loop

Happy New Years Indonesia and China


Liar Loop was my first go to for the number 2 and it worked out well. I had been trying to make Liar Loop puzzles without the number 1 for a while, but I never got any good result out of it. As it always led to having to use a high amount of 2s to counteract the missing 1, I figured it should be possible to create one with all 2s. It took a lot of tries to get it to be unique though. It was very common to end in a situation where you'd either have a non-unique puzzle or were forced to use a section of 2 in an area.
The resulting puzzle is of medium difficulty, although it is probably harder if you haven't done the genre before. Check out some of the others on my blog if needed. Very little chance you'll encounter these anywhere else.

2. Liar Loop

Draw a closed loop through all squares by running horizontally and vertically. The loop doesn't touch or cross itself. The numbers in a boldly marked area indicate that the loop never runs through this many cells consecutively. Whenever it passes through the area it always runs through either more or less cells than the given number.

Puzzle #80: Double Back; Triple Back

Happy New Years Japan, South Korea and the rest of Australia

At least this time I might actually be addressing multiple readers.

For the number 3, Double Back instantly sprang to mind. I had already done it with different numbers in my Four Colour Loop puzzle. I'm not the first to do Triple Back, as it has appeared on Palmer Mebane's blog as well. I like how this one turned out. I think once you get started with this puzzle, it shouldn't cause too many problems.

3. Double Back; Triple Back

Draw a single closed loop through all cells in the grid.  The loop must pass through each boldly marked region exactly thrice.

Puzzle #79: Tapa; Total 4

Happy New Years Australia.

I know, it's not New Years in all of Australia yet. Countries with multiple time zones are annoying.

I thought 4 would be a nice number to use in tapa. I tried to make a Maths Tapa with operations. But I realised that with only 4s, I had a lot of trouble creating openings. So instead I changed it a little and basically turned it into a mix between Tapa and Killer Sudoku. It doesn't add very much to the genre as many of the clues can be figured out instantly. I still like how the puzzle turned out though. Medium difficulty. Figuring out the opening is probably hardest.

4. Tapa; Total 4

Colour some cells to create a single contiguous shape. The shape can't have any 2 by 2 coloured areas. The clues in the grid tell you how many consecutive cells around it have to be coloured. If there's more than one digit in a cell, the groups of cells have to be seperated by at least one empty cell. Cells with clues remain empty.
Additionally, replace each question mark by a positive integer. Each clue square has 4 squares coloured around it.

Puzzle #78: Nurikabe; No Repeat.

Happy New Years Samoa and New Zealand.

I am almost 100% sure people aren't reading my blog there, but as they are the first, I figured i'd include them.

I don't think there is much of a surprise that this puzzle incorporates pentominos. I've always liked pentomino based puzzles. I think it is because the logic puzzles allow me to actually pack all 12 pentominos. This was one simple puzzle that stumped me a lot when I was young.
At first this was going to be a Shape Nurikabe, which Thomas Snyder used in his 20/10 Decathlon. Except I ran into the problem that it is pretty hard to fit 12 pentominos in a grid and create a valid Nurikabe grid. As I didn't manage to even create a valid grid, I changed the puzzle a bit. Instead I just went for no 2 islands having the same shape. this made things easier for me. The puzzle is of medium difficulty.
Also, if someone has a good suggestion for a name, I'm completely open for it.

5. Nurikabe; No Repeat

Determine for each cell if it's part of the stream or an island. Each number is part of a single island of horizontally and vertically connected cells, which size is equal to that number. Islands can't touch eachother horizontally or vertically. The cells not part of an island form the stream. The stream is a single connected area, which doesn't cover any 2x2 areas anywhere.
Additionally, no 2 islands have the same shape. Rotations and reflections are considered the same shape.

Puzzle #77: Heyawake

This was for a long time going to be a Ripple Effect or Country Road puzzle. But I didn't manage to do with either what I was aiming to do. Then I went to Heyawake as big clues can appear in a limited number there. I tried a few times and this was the nicest that came out of it. This puzzle is of medium hard difficulty. The 6 areas can't be determined quickly, but some deductions can be made to solve the rest of the puzzle, till finally the 6 areas also fall.

6. Heyawake

Paint some cells black. Black cells are not allowed to touch eachother on the sides. The remaining white area has to be connected. The white area can't span more than two consecutive rooms in a single row or column. The numbers in the rooms indicate how many cells are to be painted black.

[Edit: Another uniqueness issue fixed; it's not turning out as a good display of my construction skills]

Puzzle #76: Arrow Sudoku

Even though it's supposed to be a lucky number, it didn't bring me much luck in construction. I've tried using this number in numerous genres, but none of them really worked out. I wanted to add a second Sudoku puzzle and I went to Arrow Sudoku as I always enjoy them. It still took a long while to find a nice layout which could use only 7 clues. I'm happy with the end result. Difficulty-wise I find it hard to say, but I would call it challenging at least.

7. Arrow Sudoku

Place the digits 1-9 once in every row, column and 3x3 area. The digit in each circle equals the sum of the digits along its arrow. Digits are allowed to repeat along an arrow as long as it doesn't conflict with standard Sudoku rules.

Puzzle #75: Island

On first thought I was planning to make number 8 a Ken Ken puzzle. The problem is that I am not very good at making nice ones. After trying to find something else, I turned to Island. I figured all the same numbers for an Island puzzle could be interesting. I think the result worked out nice. It's probably the easiest Island puzzle on this blog so far, so I'm hoping people will appreciate the genre a bit more with this one as the difficulty of the previous ones has broken up most people so far. I guess I need to find a better way to judge the difficulty of these puzzles. I figured it was a relatively simple idea I used, but I think it wasn't.

8. Island

Fill in some cells to form a single island. The cells with numbers are part of this island. The numbers indicate how many unnumbered cells can be reached from that cell by moving horizontally or vertically. Numbered cells block access.

[Edit: Fixed Uniqueness issue)

Puzzle #74: Anglers

It took me a while to find a genre to satisfactorily apply the number 9 to. After going through a bunch of puzzle tests and puzzle sites I stumbled across Anglers. I've always liked Anglers puzzles, so it seemed like a good type. It worked out well. The puzzle isn't too hard.

9. Anglers

The digits on the outside represent anglers. Each angler catches one fish. The digit indicates the length of their line. The lines run by connecting the centers of cells horizontally and vertically. They don't touch or cross eachother.

Puzzle #73: Killer Sudoku

This puzzle is the one that started the whole idea of the count down. I was trying to make a Killer Sudoku with all the same sums. When I had seen a few people post a Christmas contest this year, I figured I could make a nice New Years countdown set. That's when I focussed on making one with all 10 cages.
I had first tried to make one with 1-9 but i couldn't get that right. When I attempted it with 0-8, it instantly became more productive. This puzzle is on the harder side, but I don't think it will stump the better solvers.

10. Killer Sudoku

Place the digits 0-8 once in every row, column and 3x3 area. The numbers in the dashed area indicate the sum of the digits in that area. No digits are repeated within any dashed area.

New Years Countdown

I´m sorry I haven´t been very active lately. It´s been a busy few weeks around the holidays. But I´m making up for it tomorrow.
I´ve seen some blogs feature a Holiday and Christmas special. This inspired me to write a series of puzzles as a New Years Countdown. The puzzles will be posted on regular intervals throughout the day, starting tonight at midnight CET and finishing at the start of 2012 CET.
So for those who have some time left over tomorrow, I hope you can enjoy some of these puzzles. For those who don´t, which I can completely understand, I hope they are a nice start to 2012.

Puzzle #72: Seethrough

I've seen this genre under a variety of other names: Doors, Walls, Open Office. I'm using this name as that is what I've always known it under. It was called Doorkijkje in Breinbrekers.
This puzzle was inspired by a particularly nice puzzle at the WPC. It appeared in the Evergreens round and was atypical for this genre (like all puzzles in that round). That puzzle contained only the number 1 as clues. This one has numbers 1-3, but the logic involved is very similar to that one. I think this is a more challenging puzzle to solve though.

Rules for Seethrough

Rules: Seethrough

Draw some walls inbetween the squares. The numbers in the squares indicate the total number of squares visible in horizontal and vertical direction from that square. There can be no isolated squares. This means that you should be able to reach all squares by moving horizontally and vertically.

Puzzle #71: Ripple Effect

I've always liked small challenging puzzles over large puzzles. I usually don't see much in a large puzzle that couldn't have been put into a smaller puzzle. I tried working on larger Ripple Effect puzzles, but I didn't seem to really be able to put anything in them I couldn't fit in a smaller size. So this one is a bit smaller than my previous ones but still challenging.

Rules for Ripple Effect

Puzzle #70: Tapa; Double Back

This is a new Tapa variation as far as I'm aware of. I had tried this idea before, but had trouble getting it to work. I now tried to it again and now understand how to make it work. I think the idea works very nciely now and brings some different logic to Tapa.
As the name suggest it has a similar idea as Double Back, but then in the Tapa format. The Tapa has to visit every region twice. Hope you enjoy it.

Rules for Tapa

Standard Tapa rules. Additionally, the Tapa has to visit every black bordered region exactly twice.

Puzzle #69: Four Colour Loop

This puzzle is a unique mix of four different genres: Maxi Loop, Liar Loop, Double Back and Country Road. I haven't ever seen genres combined in this way before. I've combined them by using the Four Colour Theorem. This theorem states that when a plane is split up in different regions, you'd only need four different colours to colour all regions without having any regions of the same colour touching by a side.
I'd been thinking of using this for a while, but it was hard to find a good set of puzzle rules that would work in a single puzzle. When I finally had four rules I thought would work, it took a while to even get a solid opening that would get the puzzle going. It took me a long while to get a good puzzle. I had to edit the puzzle a bunch of times as I kept running into mistakes I had made while constructing. I've worked on this puzzle on and off for a few weeks. I hope you all enjoy it. I'm warning you that it isn't easy, but it is completely logically solvable. It will probably take a while to see how the rules interact and what restrictions there are to assign the right rules to the right regions.

Four Colour Loop

General rule: 
Draw a single closed loop by connecting the centres of cells horizontally and vertically. The loop doesn't touch or cross itself. The grid is split up into different regions. Each region obeys one of four rules. No two regions with the same rule touch eachother by a side anywhere. They are allowed to touch by a corner.

Region rules:
Country Road:
The loop enters and exits the region once. The number in the region indicates the amount of cells the loop runs through. (Note: This means the loop doesn't run through all cells in the grid)

Double Back:
The loop runs through all cells in the region. The number in the region indicates the amount of the times the loop enters and exits the region.

Liar Loop:
The loop runs through all cells in the region. The number in the region indicates that the loop never runs through this many cells consecutively when traveling through that region. It is always more or less.

Maxi Loop:
The loop runs through all cells in the region. The number in the region indicates the highest amount of cells the loop runs through consecutively when running through this region.

Click to enlarge

Puzzle #68: Shakashaka

The first time I encountered this genre I really didn't get it. I had no clue how to approach it, let alone solve it. It wasn't till I encountered a puzzle on Mathgrant's blog, which had the four triangle layout that I managed to get a hang of it. I still find it funny how something cimple as a different layout or a different notation system can completely change your experience of a puzzle type.
When I understood how to work the genre, I started noticing it was actually a really fun genre. I hadn't encountered this kind of logic in any genre before. I've been working on a few puzzles. I find it hard to make nice flowing puzzles sometimes. I don't find it hard making really hard puzzles though. I've already discovered some interesting patterns that can be exploited. This puzzle is a bit easier though. It flows a bit more naturally.

Rules for Shakashaka

Rules: Shakashaka

This genre was developed by Nikoli.

Colour triangles in some squares so that the remaining white space are all shaped like rectangles. The triangles have to split a square into two equal size rightangled triangles. The numbers in the black squares indicate how many of the four adjacent squares are to be coloured with a triangle.

Puzzle #67: Slitherlink

And this is the last puzzle that featured in my set of the 24 Hour Puzzle Championship. Somehow I don't see many people being surprised that it is a Slitherlink puzzles. This has always been one of my favourite genres. It just seems to work well with how I like to solve and design puzzles. I decided to make this one on the easier side. A lot of familiar patterns and short term inner loop deductions. It was one of the lower scoring puzzles in the test and meant as a nice opening puzzle to the test.

Rules for Slitherlink

Puzzle #66: Liar Loop

So, this genre was developed while making this set. I was originally planning on putting in a Maxi Loop puzzle. But that ended up turning into a new genre. I was really happy with how the genre and the puzzle turned out. The test solving got positive feedback as well, so I figured I'd have a good new type. I first thought of keeping the genre only to the 24 hour puzzle championship, but as I had fun designing them I decided to just make one for the forum too. That way someone who followed my blog got a little advantage in the championship. That might be a tad unfair, but following my blog should be worth something.
This puzzle can also be used to get some practise in with Liar Loop solving. This will be handy for the puzzle that I will be releasing for Sinterklaas on monday. It's my present to you. It was originally planned as puzzle 50, but I didn't come close to acchieving that in the amount of time I had.

Rules for Liar Loop

Puzzle #65: Penta Sum

This is one of those standard genres for people who solve the Dutch magazine Breinbrekers. I always like them. And as it added come arithmetic to the puzzle set. I had never actually designed any before. I wanted to make it so there were no equal adjacent digits in the grid, in which I succeeded. Obviously I went for a sum of 24 for this puzzle. I though the grid layout made the place to start obvious, but I don't know you all will agree.

Penta Sum

Divide the grid into the 12 pentominos. The 5 digits in the pentomino must add up to 24. (The example uses tetrominos and the sum is 10.

Puzzle #64: Island

I decided to include this genre because the solving techniques are different from any genre. I figured this would lead to a more varied solving experience. I think many people still have trouble with the genre though, from what I heard back about this puzzle. This is probably because the solving works different than most genres. So there isn't too much to carry on from having done similar puzzle types. What you have to remember mostly, is that you have to create a single connected area. For this you have to take two things in mind. The first is the minimal distance between different clues to see how they can connect. The second is the maximum size of isolated areas can be placed. This puzzle uses the second technique more than my other puzzles so far.

Rules for Island

Puzzle #63: Sudoku

I somehow didn't think a set would be complete without a Sudoku. I first thought of putting in a variant, but I was too lazy to actually make a Sudoku. I still had this puzzle lying around, which is the only successful 20 clue Sudoku I have ever made. I thought it was relatively tricky, but it doesn't give so many places to start. So I figured people would quickly start looking at where the openings were.

Rules for Sudoku

Puzzle #62: Password Path

This puzzle type I've always liked. I hadn't really seen many of them in a while, so I thought it would be nice to put one in. I found it funny to then see that this puzzle type popped up in the WPC too as the instruction booklet was released after I had made this set.
I made a few of these puzzles and also had one that use 24HPC as the password, but that turned out a bit harder than I wanted. I didn't want this one to be too hard. It is one of the lower scoring puzzles in the test. I don't expect this puzzle to have cause many problems while solving.

Password Path

Draw a path that runs from the left top corner to the right bottom corner through all cells once without touching or crossing itself. The path can run horizontally, vertically and the diagonally. The path will run through the letters in the password in order, in the following way P-A-T-H-P-..etc. (B-R-A-M-B-.... etc. in the example).

Puzzle #61: Ripple Effect

As I've had a lot of fun designing Ripple Effect puzzles in the last months, I couldn't resist putting one in. I know my puzzles are generally harder than most, so I gave this puzzle the most points. There was a Ripple Effect puzzle distributed at the WPC which was seemingly harder than mine, but it was designed in a different way than I do.
I have previously said I wasn't sure how to design puzzles with given numbers. Mostly my puzzles with given numbers will just have them to make the end of the path unique. This one is different though. I placed these numbers in the start of the puzzle and then start designing the cages so that these numbers would instigate much of the path. I think it worked out really nicely and was worth all the points in my opinion.

Rules for Ripple Effect

Puzzle #60: Line of Sight

I still really love this genre. They are just fun to design and I think they are fun to solve. So I figured to really represent my taste in puzzles, this would be a good puzzle type to put in. I tried to make this one flow from the opening. I'm not sure how people found it in competition. It might be a bit hard to get into if you've never done them before. This ended up being the highest scoring loop puzzle.

On an unrelated note, I haven't actually made any puzzles since coming home from Eger. I'm not sure when I'll get started again but I'm a bit inspirationless at the moment. I hope to have some puzzles ready after this 24 hour puzzle championship run down though.

Rules for Line of Sight

Puzzle #59: Penta Maze

I'd had this idea a while back already. I wanted to do something with mazes to turn non-unique mazes into unique mazes by placing shapes in them. I thought this was the easiest way. I found it somewhat funny to see the idea pop up in reverse in this year's USPC. This idea seemed like something different that would fit in well in a varied set.
I thought the puzzle worked out nice, but I haven't really heard any comments on people who tried to solve them. The starting logic is somewhat tricky, but I think the most obvious thing to start with.

Rules for Penta Maze

Rules: Penta Maze

This genre was developed by me.

Place all pentomino pieces in the grid so that they don't overlap any walls or eachother. Then draw a path that runs from Start(S) to Finish (F) that only runs over the pentomino pieces. The path crosses each pentomino piece once.

The example uses tetromino pieces.

Puzzle #58: Latin Pointers

So I have already professed my love of Naoki's genres already, so I figured I should put something new from him in this set as well. I came across these puzzles a little while before designing this set and absolutely loved the idea. I've always liked Pointers (named Japanese Arrows at the WPC) puzzles, even though I always find them very challenging. This genre combined the logic with Latin Squares. Therefore the name, Latin Pointers. Naoki named the genre mount, but that didn't really sound right to me.
Neither puzzle is very hard once you get the logic involved. I think this type helped the set become more diverse logicwise.

Rules for Latin Pointers

In both puzzles place the digits 0-3 once in every row and column.

Rules: Latin Pointers

This genre was devoloped by Naoki Inaba.

Place the digits 0-n once in every row and column as indicated. In each arrow there will be a digit that indicates how many digits the arrow is pointing at.

Slitherlink Pattern Guide

This is an introduction to number patterns in Slitherlink. It's not a complete guide to how to solve these puzzles. It's about patterns I think are handy to recognise as it makes solving these puzzles easier. There's a few patterns that are very common, which most people who solve these puzzles are aware of. This is because they show up in about every other puzzle. I like to use the more unfamiliar patterns in my puzzles as it gives people new things to learn. In my opinion it doesn't actually make the puzzles more difficult, just takes more effort to solve as you have to discover the patterns first. If you already know them, they're not actually harder.

Puzzle #57: Dice

This is a puzzle type I've always liked. There isn't too much variation in it, but they're always just fun to solve. It's just the kind of logic you have to use that makes them fun to me. As the logic is different to most genres I figure it is always a good type to throw into a puzzle mix. I tried to add them to my puzzle test, but I think I ended up making the wrong choice in taking them out there. I think I should have taken the Outside Sudoku/Skyscraper set out in hindsight.
I have a feeling the minimal number of clues needed for a 4 dice set with 24 different letters, is 13 words. I have no way to prove this, I just always make the puzzle unique with the 13th word. I have a feeling someone with programming skills could verify this. It's one of those questions that pop up in my head once in a while. Johan de Ruiter already once confirmed my question about the existence of unique 4 by 4 kakuros.
This puzzle isn't too hard. The path through it runs very smoothly, which is why I didn't have it score too many points in the set.

On an unrelated note, I will be posting the Slitherlink Pattern Guide I had mentioned in Puzzle #51 later today.

Dice

You are given a set of 4 dice with letters on them instead of numbers. Each side has 1 letter on it. The given words can be rolled with this set of dice. Determine the orientation of the 4 dice.
The given example uses 3 dice.

Puzzle #56: Yajilin

As might be expected, I also put in a few Loop based puzzles as those are my favourites.As my small Yajilin puzzles have all gotten a lot of positive feedback, I thought it would be good to put one in the set as well. I was really happy with the way this puzzle worked out. I started as I start all my Yajilin puzzles by defining the squares that will contain clues. Along the way I got to a nice unique puzzle, but hadn't used the 2 corner squares. I couldn't place clues in them, without ruining the logic I had built in. So I decided to keep those as empty clue squares and not let the loop run through them.
I think this puzzle is a little bit harder than the previous 2 10x10 Yajilin puzzles I have posted.

Rules for Yajilin

There's an additional rule, that no black bordered square can be used by the loop.

Puzzle #55: Penta Pair and Penta Line

I'm posting 2 puzzles today. This is partly because I feel that posting only the Penta Pair puzzle would be a bit silly. They are both Pentomino puzzles. I had a few puzzle ideas ready for a test I was thinking of making, but that never really got off the ground. I might try that again next year as the theme is great. I put in some of the ideas in this test as I thought they were fun and it provided a few shape based puzzles.
The Penta Pair puzzle is a somewhat silly variant on the Pentomino Puddles puzzles. I have never been a fan of Pentomino Puddles puzzles, but I did like this twist on it though. I figured it would be a quick easy points, which you could get if you needed a short break or had a bit of time left at the end. I made a bunch of these puzzles and I think this was a really nice looking shape.
The Penta Line puzzle is just a simple pentomino grid variant. I hadn´t really ever seen the puzzles like this when I made it but have come across a few of them since I made it. This idea was the first draft for my LMI test, but I ended up going with a more traditional Pentomino puzzle type. I figured I could used it for this one now. I rated this puzzle a bit higher as the logic felt trickier to me than other puzzles.

Penta Pair

Determine which 2 pentomino pieces can´t both be placed in the grid without overlapping. Rotating and reflecting is allowed.
I´ve added an example that uses tetrominos.

Penta Line

Place all 12 pentominos in the grid. Rotating and reflecting is allowed. The pieces aren´t allowed to touch eachother, not even diagonally. Certain parts have already been placed.
I´ve added an example with tetrominos.

Puzzle #54: Sum Skyscrapers

Of course I needed to add some Latin square based puzzles. I also tried to fit in some arythmetic based puzzles in there. Sum Skyscrapers have always been my favourite variant, so it seemed like a logical addition.
The first puzzle I tried to make the clues on each side to add to 24, except how much I tried I couldn't get it right. This was the nicest result that came out of the attempts.
The second puzzle is a harder one. I was really happy with how this one worked out.

Rules for Skyscraper

In this variant the numbers on the outside indicate the sum of the visible digits.

Puzzle #53: Word Nurikabe

I also wanted to put in some puzzles with letters. But I generally have a lot of trouble designing puzzles with words. I tried putting in some word search and scrabble like puzzles, but they just didn't come out in any pleasing way. So i thought of using words in other genres I could work with. Nurikabe ended up being a nice choice. The trick of course was to make sure that the letters couldn't be all directly assigned to a word, because then the number of the island would be instantly known and it wouldn't be any different than a normal Nurikabe.
The design ended up really nice, with the word choice being related to the event and the puzzle.

Rules for Nurikabe

In this puzzle the number clues are replaced by letters and the islands by words. The words that have to be placed are listed on the side. Each word has one letter given. The words have to be placed so that they can be read by moving horizontally and vertically along the squares. check the example below in case something isn't clear.

Rules: Nurikabe

This genre is developed by Nikoli.

Determine for each cell if it's part of the stream or an island. Each number is part of a single island of horizontally and vertically connected cells, which size is equal to that number. Islands can't touch eachother horizontally or vertically. The cells not part of an island form the stream. The stream is a single connected area, which doesn't cover any 2x2 areas anywhere.

Puzzle #52: Heyawake

I've realised I have 19 puzzles all ready for people to solve. I figured I might as well start posting them here. I made a puzzle set for the 24 Hour Puzzle Championship, which was held on monday. Now it's over I figure I can start sharing them with everyone. Therefor I'm going to post these puzzles here. This way I can also tell a bit about them, instead of you all just getting the booklet. There will be a few new ideas by me I used in the test and a few ideas I got from other people that aren't actually seen very much online.

Rules for Heyawake

I'm going to open this with a standard Heyawake puzzle. I needed a few more familiar types in the test and this one seemed like a good one to incorporate a nice 24 theme in. I didn't want it to be hard, so I chose some more standard cage shapes to go with the numbers. The 3 by 3 and 5 by 2 cages for the 4s seem to be very frequent in puzzles. I designed the puzzle with those at the start and tried to model the rest of the cages around them. This one is easier than the others I have posted so far. It's one of the lower scoring puzzles in the test, although for experienced Heyawake solvers it was probably a quick pick up.

Puzzle #51: Slitherlink

After the WSC and WPC my puzzle energy has been really drained. I don't think I'll post regularly for a while. This puzzle is the only puzzle I wrote during the whole championship week. It is meant as a Slitherlink Pattern Tutorial. I wrote is as a response to my teammates asking if there were patterns they didn't know. So I showed a few I like to use in my puzzles. Then I decided to just create a puzzle around all of the ones I had shown. I added one or 2 more little tricks I also like to put in. It's not a complete package of tricks for my puzzles. I have put some others in puzzles too. But figuring out all patterns in this one should get you along a fair bit in my Slitherlink puzzles.

Rules for Slitherlink

Puzzle #50: Ripple Effect

Returned from the World Sudoku and World Puzzle Championships, seemingly in one piece. A few bruises and scrapes over my body is all I have left over from it. Finished nicely in 5th place after the 2 days of puzzling, which came as a surprise to me. I was expecting to have to battle really hard for a place in the top 10, but always remained comfortably in 4th or 5th place through the 2 days. Maybe on location competitions just suit me better than online competitions. Or maybe it's just that I am far more focussed sitting on a desk in relative silence opposed to solving online competitions in a lazy chair with the tv in the background. A bit too bad on my play off performance. A lousy No Four in a Row solve, a dumb Battleships solve and a stray circle in my Pointing at the Crowd puzzle, made me just miss out making the 7 person cut. I'm happy with my overall performance none-the-less.

Now back to actual puzzles. I know some people might have expected something special for number 50. I have been working on two ideas which were far harder than I had imagined to complete. I'm not even sure if one of them will ever work out, but it's nice to try challenging myself. As I couldn't complete either of them and I hadn't posted anything in over a week, I figured I should at least post something.
I've had a few of my puzzles published in Akil Oyunlari. It contains four Turning Fences and two Ripple Effect puzzles by my hand. Some of the Ripple Effect puzzles I had submitted were considered too hard for the magazine. I had somewhat expected they might be, but then again it said I could make some puzzles as hard as I wanted. I really loved the design of those puzzles, so I'm posting them here now. These two Ripple Effect puzzles have some very noticable designs. The first has a cute four by four square in the middle, which I've used in other puzzles before. The second has a nice stairs pattern in the right bottom corner. I hope you enjoy them.

Rules for Ripple Effect

Puzzle #49: Slitherlink; Liars

I'm not sure how much I will post in the next week or so. I will be flying out to Hungary on Sunday to participate in the World Sudoku Championships and World Puzzle Championships.

For this puzzle, the opening is trickier than my previous Liar Slitherlink puzzle.

Rules for Slitherlink

As an additional rule, exactly one clue in every row and column is incorrect.

Puzzle #48: Yajilin

Rules for Yajilin

My small Yajilin puzzles seem to be very much appreciated. So here's another one. Like the other one it's not too hard and it's not too easy. So hope you enjoy it.