If you love slide puzzles you certainly have heard about the Grabarchuk family and their amazing creations. Some of the best slide puzzles I've tried and own in my collection are from them and I plan to get my hands on several more in the future. For now, let's concentrate on this original concept by Serhiy & Peter Grabarchuk, the Sliding Stones - Could easily be a name for a Rock band...

First, before talking about the concept, I'd like to mention the great craftsmanship that went into the design. There are five different types of wood, four in the pieces and the remaining one in the tray. The resulting visual effect is rather beautiful and elegant. The metal button in the square piece is the perfect touch on a flawless design, but also practical, since it makes it easier to move. The size is average for a slide puzzle, with dimensions of 14 x 10cm (5.5" x 4").

The puzzle consists of five pieces, four identical l-shaped ones and a square one. The starting position has the four identical pieces in a square form with each one occupying a corner and the square piece is in the middle below the two bottom pieces. The goal is to slide all pieces, without lifting a single one from the board, so that the square fits inside the empty space in between the four pieces. There are 22 possible moves for an optimal solution, but the important thing is to achieve the final state. With practice, you should be able to achieve the minimum step solution.

There's something you need to take into account when attempting to solve the puzzle. The square is comprised of four different colors, each one corresponding to an l-shaped piece. When solved, each corner of the square should be touching an l-shaped piece of the same color. The puzzle would already be difficult enough if not for the colors, but instead it just makes it even more challenging. You'll be able to put the square inside the four identical pieces in a number of times on your way to the correct solution, but finding the right configuration is quite tricky. It took me about 10 or 15 minutes to completely solve the puzzle, and only after I've discovered that the pieces can be rotated inside, depending on the position of the other pieces. This interesting solving process was a first for me, and it gave me a great rewarding feeling and sense of accomplishment. I'm yet to find the optimal 22-step solution, though.

Closing Comments:

I'm a big fan of Grabarchuk puzzles, and with puzzles like the Sliding Stones who wouldn't be a fan? The high difficulty level might put some people off, but if you stick with it and insist this might not be the last Grabarchuk puzzle you'll own. Highly recommended.

Availability: The Sliding Stones puzzle is available from Sloyd.fi for about €17.

The Grabarchuk Family are masters at creating slide puzzles. The Two Sliding Squares is a design by Serhiy Grabarchuk, and what a puzzle this is - One of the hardest sliding puzzles I've seen in a while.

The concept of the Two Sliding Squares is a bit difficult to understand at first, but it's actually pretty straightforward. The puzzle has two layers: one is made out of silver squares only and the other is comprised of blue fragments that are attached to some of the silver squares. The fragments, when placed at the right positions, will form two valid states: the first is relative to the start position and will show two blue squares, a small one and a bigger one. The other state is the end position, or if you will, the object of the puzzle, which is merging those two squares into a larger unique square. This task has to be done solely by sliding the pieces inside the tray and no piece shall be lifted from the playing field.

Now, regarding the presentation and overall quality of the puzzle... If I say Bits and Pieces, can you guess what my opinion is? - Well, it's not good. This one's in very bad shape, actually, and might be of the worse puzzles from them in my collection. You can get an idea of how bad it is by the pictures - Kind of looks like it has been in a war zone. The pieces are full of marks and blemishes, and have lots of excess glue used for the two-part pieces. It's pretty clear that no extra care went into the finishing touches or even by simply cleaning it to prevent the excessive glue from ruining the otherwise great appearance. You can see that the rough concept is there: anodized aluminum pieces and a black wooden tray make for a great combination, but they failed to produce a flawless puzzle. From what I've seen in other pictures from fellow collectors, it's not just mine that has all these problems. They are present more or less the same way. Sloppy manufacturing, plain and simple...

So why would I get a puzzle from Bits and Pieces knowing beforehand that I shouldn't expect anything good from them? - Simple answer: because it's a Grabarchuk puzzle and I like to support talented designers. If you care more about the concept and are willing to overlook the manufacturing flaws, you're left with a fantastic puzzle. The idea is very original and nothing like I've ever seen in a slide puzzle.

Your task is to go from one position to another, but between the two there's actually about 50 different moves. The provided solution shows just 45 moves, but I reckon it must have taken me over 100. This is rated by PuzzleMaster as a level 8/10, although from my experience it feels more like a 9, as the sliding moves aren't as simple as you're used to in a classic slide tile puzzle.

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In this 4x3 grid puzzle, you start by removing any of the plain silver squares to make room for the others to slide back and forth. However, as you make your very first movements, you'll encounter the first setbacks: some of the pieces will only go to a certain position until they no longer can be moved any further. This is due to the configuration of the pieces, because the blue parts are glued to the silver squares and most of the times they overlap to the neighboring space, not leaving enough room for another piece to move past it. Planning ahead, as you can imagine, is crucial to keep the pieces moving albeit sometimes quite irritating and frustrating, but extremely satisfying.

Closing Comments:

If you like to collect puzzles for their beautiful presentation and overall appearance, this may not be the right one for you. Bits and Pieces have managed, again, to ruin what could have been great to a mediocre puzzle, to say the least. The concept by Serhiy Grabarchuk is beyond amazing, though, and if you like slide puzzle, give this one a try. It's worth it even if the presentation leaves much to be desired.

Availability: I got my copy of Two Sliding Squares from PuzzleMaster, but they are sold out at the moment. Check back again soon, as they restock regularly.

Links:

The Grabarchuk Puzzles Family

Online Slide Puzzles by Serhiy Grabarchuk

The Cast Puzzle Series may be the hallmark product produced by Hanayama, but they have many other different challenges and they're very interesting as well.

The Puzzle Impossible is a good example of the Hanayama's quality and originality. It was designed by Ukrainian Serhiy Grabarchuk Jr. and it's a Slide Puzzle with a twist. This ingenious design depicts the numbers from 1 to 9, in a 3x3 grid, in the digital form of seven-segment display characters. The "twist" is that the segments from each number aren't all printed on the transparent tiles - some of them are marked on the tray. This way, as you slide each tile inside the frame, the number appears to be scrambled as if your digital wrist watch/alarm clock was out of whack. This cool effect is what makes the design so appealing.

There are three main challenges that you can attempt to solve (just by sliding the tiles). The packaging of the puzzle is entirely in Japanese, however, it's easy to recognize by the pictures what needs to be accomplished. The first challenge is common to every slide puzzle - just scramble the tiles and then return them to their original pattern. This is relatively easy for anyone that has solved the classic 15 Puzzle. The next two challenges are exactly what gives this puzzle its "Impossible" connotation.

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The second challenge, or first of these two impossible tasks, requires you to swap the last two tiles by making a sequence of 1, 2, 3, 4, 5, 6, 7, 9, 8 and solve it into the correct arrangement. Now, if you're familiar with the slide puzzle concept and history, you know that the presented challenge will create a parity error, because it requires a transformation of an even combination to an odd one. But there's a way to overcome that by taking advantage of the puzzle's concept. Spoiler ahead: If you look closely at the photo of the tiles outside the tray (above this paragraph), you can see that the segments that form the number 4 are exactly the same as the ones on the number 9. By making the "4" and "9" tiles swapping places, it becomes possible to solve the puzzle. There is a minimum of 18 moves to solve this.

The final challenge is another impossibility: from the solved state, you are now required to make an arrangement of the tiles, also just by sliding, so that it shows the sequence 1, 2, 3, 4, 5, 6, 7, 8, 3. Again, how is it possible to have two of the same numbers appear on the same frame? - There are two solutions for this, one that uses a minimum of 24 moves and another with only 20 moves. Spoiler ahead: By looking again at the photo of the tiles outside the tray, there are exactly two tiles that can form the number 3 on the frame. One is being used by the "3" in the first row, and the other is being used to form the "7". The first think that comes to mind is, "how to show in the same frame a 3, a 7 and another 3?" - The answer lies in the way you can form a 7. The first is just with three segments and the other, the solution, is with four (see the difference in the photo, below right). So, the first solution requires a swap of the "3", "7" and "9" tiles to the positions of the "9", "3" and "7", respectively. The second solution, more efficient, requires a swap of the tiles "4", "7", "9" to the positions "7", "9", "4", respectively. Intuitively, it would be more practical to just swap the number 7 with the 9, but it would result in another parity error.

I have seen this puzzle for the first time, a while ago at Rob's Puzzle Page, but whenever I tried to buy one, I couldn't find it anywhere. That was until a couple of months ago, when I found one for sale at eBay. I had to get it before it was too late again. At the time I bought this one, the seller had another copy, but now, unfortunately, it seems to have gone. I checked Hanayama's website, but couldn't find it there either. I believe they're being sold at Amazon Japan, but I'm not sure they send overseas. It was apparently a limited production run and now it's harder to find.

It seems that almost anything was attempted with the sliding puzzle concept before, but Serhiy Grabarchuk Jr. proved that it's still very possible to come up with an original and amazing design... And associated with Hanayama's quality,  you can't go wrong with the Puzzle Impossible. Definitely recommended for the Sliding Tile enthusiasts... If you find one.

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The Cast Series are metal disentanglement puzzles made by Japanese company Hanayama.

The first puzzles were released in 1983 and since then, more than fifty different designs have been made. Some of them are remakes of old classics that were popular in the late 19th and early 20th centuries. Puzzle designers Oskar van Deventer and Vesa Timonen have contributed with several designs through the years and many more had their designs picked up by Hanayama.

Each puzzle has its own theme, its name and the company's engraved, which makes each and every one of them, very unique. Their packaging presentation is exquisite and it's very nice to see, in the box, the correspondent Japanese character for each one. Also, the build quality is top-notch, with very nice finishing touches. If you're a collector and like to have them displayed on a shelf, their box is a nice way to do this.

There's six levels of difficulty, from the easiest (like the Bike) to the extreme (like the Elk). The goal is always the same. Can you take them apart? Some of them are so difficult that sometimes you don't even know where to begin. And, as if it weren't enough, you have to put them back to their original state when you solve them. Don't be fooled, as some might be even harder to assemble back together than to take apart, because when you're trying to separate their pieces, you might not pay attention to the method that you used or you may as well got lucky and you don't know for sure what you did to solve it.

Next, I'll present some of these cast puzzles, the ones that I currently own and solved. I managed to solve most of them (six out of nine), but I'm still trying to figure out those three that keep intriguing me.

Cast News (針)

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This was the puzzle that got me into the Cast fever. Designed by NOB (Nobuyuki Yoshigahara) and released in May 2003, the design is one of the most beautiful from Hanayama's series, with the American Text font used for the N.E.W.S letters.

This is rated as difficulty 6 (the maximum), although I was able to solve it in a couple of minutes, mainly because I recognized the mechanics involved from a similar puzzle I solved a while back (X Marks the Spot). When I heard the pieces move around inside, I knew what I had to do in order to open it. If you're unfamiliar with this concept, then you'll have a hard time figuring out what's going on inside it. It's still a wonderful puzzle and very fun to watch your friends trying to take it apart.

Solution: Click here to download the solution.

Cast Bike (道)

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The Cast Bike was released in 1994 and it's a remake of an old classic from the end of the 19th century and I must say, perfectly made, as it turned out to be a very elegant and neat design.

This one is actually very easy to solve. Rated as difficulty 1, it uses the same principle as the ABC Puzzle, which is to follow the maze on the bike with the ring, through the entire length of the puzzle and free it from the frame. It's a little harder than the ABC, but not that much, because you'll eventually solve it by trial and error.

It's a nice puzzle to get started in the Hanayama series and one that everyone can pick up and solve it without any frustration whatsoever.

Video: Click here to see a video solution of the Cast Bike.

Solution: Click here to download the solution.

Cast Marble (球)

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Created by Bram Cohen and Oskar van Deventer, the Cast Marble was released in April 2009. It's one of the most beautiful in the series and for someone that may see it for the first time, might not even take it as a puzzle.

It's rated as 4 in difficulty, but it can be very tricky to understand how to separate the marble from the other two pieces of the frame. This one is actually harder to put back together than to take apart, because once you separate all the pieces, you probably won't even understand how you did it. It can be very frustrating, trying to put the pieces in a way that can fit properly together into the cubic shape again. No shame in checking the solution for this one, but only for putting it together, as the main goal is already conquered...

The Marble was the only Cast puzzle so far that I've seen with a little imperfection. It has some air bubbles around it that were perhaps caused by the coating finish not to dry properly. It doesn't hinder you from enjoying the puzzle, but it's unfortunate nonetheless.

Solution: Click here to download the solution.

Cast Claw (蟹)

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The Cast Claw (or Crab), released in March 1999 is part of the Marine Series by Hanayama and designed by Akio Yamamoto. Currently, there's six different designs and they vary from difficulty 1 to 3. The Starfish is my favorite and most certainly, one of the next purchases in the Cast series.

It's only difficulty 2 and the method is similar of the ones used in ABC and Bike, in which you have to follow a path in order to release the other piece. It's harder than those two, because the final step to release it, is not so straightforward as you'd think. The design is very original, with a small fingerling as the ring.

Solution: Click here to download the solution.

Cast Coaster (結)

The Cast Puzzles are definitely a must have in every collection, not only for their beautiful designs, but also because each one provides a different challenge, leaving amazed even the ones that don't like puzzles very much. None of them comes with a solution inside, because the company believes that "you have to experience the fun and frustration in solving these puzzles". Doesn't matter how many of them you solved so far and how good you are at solving puzzles, because when you have a new one in your hands, it will make you think, for it will be so different from the others that what you did with them, it won't help you in solving this one.

I still have three unsolved, the Dolce, the Equa and the Elk with difficulties of 3, 5 and 6 respectively. With the exception of the Equa, the other two seem so simple that it's hard to think of them in another perspective. Maybe I'm missing something or I need to approach them in a different way.

All of the Cast Puzzles being sold right now are available at PuzzleMaster.