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Imagine, a padlock without a key. That would be great, because you could open it without worrying about losing its key. But, there's a downside with this puzzle lock. To solve it, you'll need at least 250 steps - hence the name of the puzzle - which can take a while to open it. However, it's a perfect way to keep something of value locked, since it would discourage any thief from attempting to rob you, lest they would get caught with the hands in the cookie jar.

The Schloss 250 has a robust body made of laser-cut wood. Four pins are held in place in the middle and stuck between the four wooden plates that cross the lock from one side to the other. The pins can only be moved from left to right, but you have to unlock their path with the correct sequence. The movement of the puzzle could be better, because it can be stuck sometimes and you risk losing your concentration. Other than that, it's very well made.

The solution is simple, but at the same time, complex. This seems quite an incoherent thought, but it's actually true. The solving process implies the use of recursive mathematics, which means it has a specific set of rules that will repeat after a while. While it can be complex due to the number of moves needed to solve it, and also extreme concentration, once you understand the repetitive nature of the solution, it becomes very simple. This is a puzzle belonging to the group of 6-ary (remember that binary has only two states, 1 or 0), which means it has six different states. Understanding this notion will help you a lot in solving this challenging puzzle.

Closing Comments:

The Schloss 250 by Constantin is a true test to anyone's patience. With its whopping 250 steps, although it can take you more, only the most courageous will succeed in solving this fiendish puzzle.

Availability: PuzzleMaster is the place to get this great puzzle. If you want a less challenging puzzle or any other from Constantin, you can browse his available puzzles.

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Made with four sliding laser-cut wooden plates, the N5 is a small puzzle, measuring just 8cm in diameter. The plates are placed in pairs perpendicular to each other. The top plates have four small mazes that have different paths, navigated by four pins. The goal is to slide the plates until you can free the small metal sphere trapped under them.

The puzzle looks a bit complex at first, but you'll soon find out that it's actually quite easy to solve, especially if you're used to sequential movement puzzles. I counted 22 moves until I could remove the sphere from the puzzle, but it could be even less. It can be solved within five minutes, and within one minute when you know the moves by heart.

I found it a bit more difficult to put the puzzle back to its original state, but I believe it was because I didn't know the moves by heart. Once you do, it's as easy to solve as it is to put it back. The difficulty level is 8/10, but I reckon it should be more about 7/10. The sequential movement is classified as 3-ary, or ternary (three states, as opposed to the binary's two states).

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I really liked the N-5 by Constantin. It's an easy puzzle to solve at any time without frustration, but still very fun to play with. Also, with just 20+ moves you can easily set it up for someone else to try it. This is recommended for beginners to practice, because there are bigger versions of this puzzle with much more moves (hundreds of moves).

Availability: You can find the N-5 puzzle at PuzzleMaster for $23.99 CAD. Check out other interesting puzzles by Jean Claude Constantin.

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Presented in a small package, perfectly portable, Jump'IN features only eight pieces, three of them stationary and five movable. The pieces are quite small, so it's not recommended for children under the age of seven. The game board features a 5x5 grid and comes with a booklet with 60 challenges, divided in five increasing difficulties. There's much here for anyone, expert or not.

The game can be a little confusing to understand at first, since there are some rules you have to understand before starting, but once they're learned, it becomes rather fun to play.

The main goal here is to have all the rabbits inside the brown holes. Since this is a sequential movement puzzle, there will always be an ideal solution with a minimum number of moves (identified in each challenge). Naturally, on your first try, you won't probably solve a challenge with the ideal number of moves, but once you know the final position for each piece it's easier to find a strategy and improve your solutions. It's also a way to improve your solving skills for the more difficult challenges that await you at the end of the booklet.

The only stationary pieces in the game are the mushrooms. Once you put them on the board you can't move them for the remainder of that challenge. As for the rabbits and the foxes, each has a different kind of movement. The foxes move by sliding them back and forth on the board, whether it's vertically or horizontally, depending on the piece's orientation. The rabbits, as expected, move by jumping around over obstacles found on the board, either foxes, mushrooms or even other rabbits. They always have to jump over a piece and never over an empty space, and always land on another empty space. To better understand this, a minimum move has to be at least two spaces, never an adjacent one. Also, a rabbit inside a hole may not be indicative of its final position, as they can move around anytime if it's necessary.

I found this game to be quite challenging, but still fun whether you're playing at a low or a high level. Because the solution involves a sequential series of moves, you have to be thinking in advance, or there will be times when you're just moving around in trial and error. This can be avoided by simply using a strategy similar to chess, where you're always a few moves ahead. It can be very rewarding to solve a difficult challenge by using logic instead of just trying to see where some particular move leads you.


Closing Comments:

I really liked SmartGames' new puzzle game. It makes you think in a different way and that's pretty good. The concept being so different from what's usually on offer by SmartGames also makes it a worthy addition to your collection.

Availability: You can find the Jump'IN game in your usual puzzle stores, like Amazon. Other games by SmartGames are also worth considering.

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Labynary is very well built from plywood slabs and acrylic on the top and bottom of the puzzle. I like the name of the puzzle, because it cleverly uses the term "n-ary", which these sequential movement puzzles are popularly known for. The puzzle has a circular shape, but the labyrinth inside is laid out in a 4x4 square grid. Scattered throughout the area of the puzzle are sliding pins that will lock or unlock the movement of any of the six sliding wood strips (four horizontal and two vertical). The goal is to free the metal sphere from the puzzle.

The movement of the strips will allow a small metal sphere to navigate through the labyrinth and eventually be freed from one of the three exit holes. These three holes positioned at the edges of the puzzle indicate the presence of three different paths, which means three mazes, or three different solutions. Sounds complicated? It should, because this is one hell of a challenge.

What makes this puzzle so complex is the number of sliding pins. With so many different things to manipulate and move, it becomes quite confusing to know which move you should make next. The puzzle has a binary concept, which means that it has two different states (1 or 0 - on or off - left or right). It seems simple, but understanding how the mechanism of the puzzle works in this binary environment will be the hardest part in your attempt at solving it. I would classify this as a difficulty level 10/10, or more likely 11/10. I don't remember ever seeing such a complex and difficult puzzle...

Closing Comments:

The Labynary will be the ultimate puzzle to test your patience levels and of course, your solving skills. Even the most experienced fans will have a hard time with this one. As a collector, it doesn't matter if it's difficult, because it's a very attractive puzzle to add to your collection.

Availability: You can find the Labynary puzzle at PuzzleMaster for $62.99 CAD. Check out other interesting puzzles by Jean Claude Constantin as well.

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One of the things that pops right out of this incredible design is its size. It measures about 21cm diagonally and features four big cogs placed at each corner. The material used is laser-cut wood, which is easier to work with, especially due to the small dents of the cogs. The movement of the puzzle is smooth and works flawlessly.

The design of the puzzle, which by the way, doesn't look like a real puzzle at all, but something from the mind of Leonardo da Vinci, is in itself a masterpiece of craftsmanship. The four wheels, or cogs, or discs, whatever you want to call them, work simultaneously if you rotate just one of them. Carved in the face of the wheels is a winding path that's being navigated by four small metal spheres. Your goal, however, is to free just one of these spheres (there's a larger hole in the frame), since the other three are there just to make your task a bit more difficult by blocking some of the movements.

This puzzle is quite difficult to solve, because it has a large number of movements required to free the sphere. The level of difficulty is 9/10, so this is a big challenge for the more experienced fans. The movement of the puzzle is classified as 3-ary (ternary, because of its three states). Solving it requires utmost concentration, as you need to pay attention to how the wheels turn and to keep the spheres in the correct path. It takes a while to get used to the movement of the puzzle and to find the correct sequence, but once you do it's easier to solve.

Closing Comments:

Uhrwerk by Constantin is a magnificent puzzle. You can play with it without even trying to solve it, just playing with the movement. To solve it, however, you should be an experienced fan, otherwise it can be extremely frustrating.

Availability: You can find the Uhrwerk puzzle at Brilliant Puzzles for $34.95 USD. There are also many other interesting designs from Jean Claude Constantin.

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As you can see from the photo, this is quite a big puzzle, considering that other puzzle locks are usually smaller. It measures 18cm x 11.5cm, which is rather satisfying for a puzzle that looks so stunning and intriguing at the same time. This lock consists of 20 pins - five groups of four - and each group of pins moves left or right. The pins don't move independently from each other, instead they move simultaneously within each group.

The design of the puzzle is what's most striking about it. It's made to look so complex that it will certainly intimidate even the most experienced puzzler. There are four different rectangular mazes in the form of sliding platforms that the groups of pins need to navigate. When you want to make a move you need to make sure all pins aren't blocking your movements. The two middle platforms are the most important since they're the ones that will be first removed. Only when they're out of the puzzle will you finally be able to remove the last two platforms, which are connected to the shackle. The platforms move vertically, which is perpendicular to the movement of the pins.

This is an extremely difficult puzzle to solve, a level 10/10, so only if you feel confident you can solve it should you attempt to do it. A beginner will most certainly feel frustrated in no time. This looks like one of those n-ary puzzles Constantin also makes very well (a binary puzzle for example), but this is not one of those. In fact, I believe that because it's not a n-ary puzzle it's even more difficult, because its sequence is not linear. It's more chaotic and it doesn't follow any specific rules. You will need to solve it step by step by always figuring out the next move, not by a predetermined sequence but by a random set of movements - like a maze! We all know that mazes aren't logic, so just keep trying until you can open the lock.

Closing Comments:

If you like difficult puzzles, Constantin has so many great ones for you that it will be difficult to choose just one. The Maischloß is a great choice if you're looking for a good challenge and a different concept. It has all the ingredients an experienced puzzler wants.

Availability: You can get a copy of the Maischloß puzzle at Brilliant Puzzles for $38.95. For more Constantin puzzles check out their other offerings.

Fans of labyrinths and puzzle boxes have a reason to love Jean Claude Constantin's new puzzle, the PLD Box (also known as Laby Box), since it combines these two distinct concepts perfectly into a brilliant and unique puzzle.

As you know, a puzzle box has a hidden mechanism or some other locking device that needs to be deciphered in order to open it. However, this box is a little different, because the locking mechanism can be seen. It's a labyrinth, but don't think it's easier than any other puzzle box. In order to open this box you have to solve the labyrinth and remove its acrylic cover.

I was pleasantly surprised with the quality and overall design of this puzzle. It is quite big and sturdy, measuring 12.5cm x 9.7cm x 6.5cm. The body of the box is made of this lighter shade of wood, almost the same color as bamboo, but I'm not sure exactly what type of wood it is. The top of the box is decorated with a geometric maze consisting of two sliding plates that move in opposite directions. The goal is to navigate the two mazes by moving the six pins up and down while pulling on the plates back and forth. Only one of the plates can be removed, as you can see by carefully analyzing the mazes. Only one of the mazes is actually linked as one continuous path. The other maze is separated into three different path that are not linked together.

The pins can't move independently from each other. They move in pairs vertically, so you have to solve both mazes simultaneously, always planning your moves strategically. With each move you'll have to move some pins up, others down, or you won't be able to slide the plate out of the box.

The difficulty level of this puzzle is very high, because of the high number of moves involved in the solution. To remove the cover you have to repeat many of the movements, as if you were following a logic sequence. Once you understand the logic behind the maze, you'll solve the puzzle in no time.

Closing Comments:

The PLD Box by Constantin is one of his best puzzle box designs. The combination of two different concepts works flawlessly and solving one will be a great accomplishment accompanied by a rewarding feeling.

Availability: The PLD Box is available at Brilliant Puzzles for $39.95 USD. There are also many other interesting Constantin's designs.

Jean Claude Constantin always excels at what he does. His puzzles are some of the most amazing concepts you'll ever find out there and a lot of them are as challenging as they come. Puzzle Locks and n-ary puzzles are a perfect combination and here, with the Schloß Dick, Constantin delivers a great looking and interesting puzzle.

This is a rather small puzzle, measuring only 10.5cm x 6.8cm (4.13" x 2.68"). I would've liked a slightly bigger puzzle, since it can be more difficult to manipulate those small sliding platforms. Nevertheless, the movement of the puzzle is still good, despite it being made from laser-cut wood (plywood).

The Schloß Dick is essentially a n-ary sequential movement puzzle, more specifically a 5-ary (quinary). It sounds intimidating, but in all honesty this feels like a binary puzzle (2-ary if you want to be specific), and therefore it's not as difficult as it looks. The puzzle consists of four sliding platforms that move vertically, while you slide a pin horizontally to match the path of each platform. The puzzle will only be open when all four pieces are slid to the bottom.

This is rated as a level 4/5, but if you're used to sequential movement puzzles, this is easily a level 3/5 or a 7 in a scale of 10. I managed to solve it within 5 minutes, and it took me even less time to put it back together. The four platforms are all different (each has ever larger paths than the previous), but once you know the sequence it's just "rinse and repeat" until you open the lock - It's recursive mathematics, so you should be OK, even if mathematics aren't your forte.

Closing Comments:

I really liked the Schloß Dick by Constantin. It's not a frustrating puzzle, and by solving it in such a short amount of time, you can solve it anytime you want a quick puzzle fix. The only fault, really, is its short size. Definitely worth a try.

Availability: You can buy a copy of the Schloß Dick at Brilliant Puzzles for $25.95 USD. For other Constantin designs click here.

Links:

Check out Goetz Schwandtner's website if you want to know more about n-ary puzzles.

A few weeks ago I reviewed the Ladybird puzzle by Robrecht Louage and Michel van Ipenburg, a perfect collaboration between two respected puzzlers that resulted in a series of pretty interesting designs. Today I present you another one of those puzzles, the Larva.

The Larva follows the same principle as the Ladybird, except this time you have two sets of metal studs that you need to guide through two independent mazes instead of two overlapping ones. The two mazes are slightly different from each other, but both sets of studs need to get to the end of each maze at the same time. You move along each maze by pushing or pulling on the two vertical bars, while sliding the mazes horizontally. It's as simple as that.

The materials used in this puzzle are basically the same as well, with trespa and acrylic. This one is a little smaller, however. The acrylic frame measures 8cm x 8.5cm (3.1" x 3.3"), but the mazes extend beyond the length of the frame, both measuring 14.5cm (5.7").

The design of the Larva is less flashy than the Ladybird's, but that doesn't mean it's less fun. I like both design approaches. While they try to differentiate the two designs by having the mazes in a different configuration, the concept is intrinsically the same. Personally, I don't see this as a bad thing, because I liked the challenge the two of them offered. However, if you didn't like one of them, chances are the other won't make you change your mind either.

This time, to remove the coin you only need to slide one of the mazes out of the way, except they're both bound by the moves of each other. The studs follow an intuitive path for most of the time but, like the Ladybird, when you get closer to the end there's a sort of dead end where it seems you can't move either maze any more. You just need to backtrack a little to make a slight adjustment and you should be fine afterwards. Resetting the puzzle is a lot easier, fortunately...

Closing Comments:

In my opinion, the Ladybird is a better design overall, but I wouldn't discard the Larva. Each puzzle has its own unique characteristics and, speaking as a collector, I would always recommend the two. You can never have too much maze puzzles...

Availability: These puzzles were made in limited quatities, so you should act quickly if you want one of these. Note also that there are two other designs by these two designers, so if you really like this type of puzzles I would urge you to get them all before they become out of stock. You can contact Robrecht at "rlouage(at)telenet(dot)be" or you can get in touch with Michel (if you don't have his contact, drop me an e-mail).

Over the years, I've come to associate coin puzzles with Robrecht Louage. No wonder, as every year Robrecht participates in the International Puzzle Party and enters one or two new designs featuring coins trapped in mazes. This year, at the 34th IPP, and with the collaboration of Michel van Ipenburg, the Ladybird was added as the newest member of the coin puzzles' family...And what a member! 

This is why I love Robrecht's puzzles so much. When I think he can't do better than last time, he outdoes himself time and again. It's difficult to choose one single puzzle as his absolute best, but at least Ladybird is up there as one of the best. Why? First, the design. You can't have a great puzzle without a proper and original design. Then, there's the actual puzzle itself. If it's too difficult, it may frustrate most people and they might give up on it. But, on the other hand, if it's too easy, people don't feel challenged enough or they don't feel they've accomplished anything. You gotta find the perfect balance.

Speaking of design, the Ladybird is a great achievement in this department. Again, one of the best by Robrecht. Also, this is one of the biggest, if not THE biggest coin puzzle yet, with measurements of 13.2cm x 11.5cm (5.2" x 4.5") (without the antennae). The materials are pretty much the same as its predecessors, the main material being trespa, with a protective acrylic panel. Unlike previous coin puzzles, the back of the Ladybird puzzle was also decorated with the bug's red and black motif, for a truer large scale representation.

As for the puzzle aspect, two similar rotating mazes in two layers make this a very fun challenge to play with. There's a 1€ coin in the top layer that needs to be aligned with the hole in the acrylic in order to remove it. For that, you need to rotate each maze, independently, while pushing or pulling on the two antennae so you can navigate both mazes back and forth. Since each maze is slightly different from one another, you have to be constantly moving them so the two paths align with each other and thus, creating a path to free the coin.

This one took me a while to solve, and it's one of those puzzles that makes you think you're very close to the end, but blocks your very last couple of steps. There's a total of 160 moves necessary to solve the Ladybird, although I reckon it took me a bit more to reach my goal, and only after 20 minutes or so. Returning to the start position is a lot easier, though, so you can easily start from the beginning and try to solve it quicker the next time around.

Closing Comments:

Robrecht Louage's Ladybird is an incredible puzzle. It nails almost every requirement of what makes a great puzzle without compromising functionality. The mechanism is simple, but works flawlessly, and being a classic maze without a complex concept, it's a nice puzzle for anyone to try.

Availability: You can contact Robrecht directly at «rlouage(at)telenet(dot)be» to ask for a copy of Ladybird or any other of his original designs.

Jean Claude Constantin is among a small group of elite designers that make the best n-ary puzzles currently in the market. Very popular among experienced puzzlers, n-ary puzzles are some of the hardest puzzles you can attempt to solve, especially if said puzzles require hundreds of steps to be solved.

Why are these puzzles so hard, you might be asking? Simple. You need lots of concentration, and that's very hard to do when we're talking hundreds of steps that need to be performed in a specific order. Lose your train of thought for a moment and you'll struggle to resume the solving process. Add that to the fact that most puzzles lack a simple way to be reset, and you're left with a hell of a challenge.

6 Bottles is my latest n-ary acquisition. The puzzle has a very original and interesting design. I haven't seen anything closely resembling it in the n-ary family. There are six identical bottle-shaped pieces that slide vertically and a bar that moves horizontally. The movement of the bar is restricted by the position of the steel balls that allow only one bottle at a time to move freely up and down. The bar itself has two slots, one deeper than the other, which also allow two bottles to be moved down at different lengths. The idea is to get five of the steel balls in the lower left slot of the five leftmost bottles, and the sixth ball in the special slot located at the far right. Once all the bottles can be pulled at the same length outside the frame, you'll be able to slide the bar all the way and remove it.

This puzzle belongs to the 3-ary, or ternary group. The number in the "ary" word refers to the states a puzzle has in its solving process. For example, the binary puzzles, which are the simplest - but not necessarily the easiest - have only two states (on-off). The difficulty, besides its n-ary group, is also given for the number of steps the solution has - the more steps, the more difficult it is.

Fortunately, the 6 Bottles puzzles is not that difficult because it doesn't have a large number of steps - still, 252 is challenging enough. The puzzle is rated as a level 9/10, but honestly, I don't believe it's that hard. It's an 8 at the most, and that's being generous.

Putting it back in its original state can prove to be equally challenging, if not more, since you'll have to perform all the steps backwards. This is why I'd love for this type of puzzles to have an easy way to be reset...

Closing Comments:

6 Bottles can be a great puzzle to train for harder and demanding n-ary puzzles. It's not overly difficult, so you can easily understand how these puzzles work and know the logic behind them. As a Constantin fan, I can easily recommend this puzzle to anyone, collector or not.

Availability: The 6 Bottles puzzle can be purchased at PuzzleMaster for about $50 CAD. Click here to browse many more Constantin's interesting designs.

About a year ago, I reviewed the first puzzle designed by my fellow blogger and puzzler Jerry Loo, the Ball in Cylinder #1. The result was a really nice surprise, considering how little experience he had at designing and manufacturing puzzles. The BIC #1 was a superb puzzle, so Jerry had his work cut out for him if he wanted to succeed with his second design. In my opinion, not only he succeeded, but he also outdone himself.

Like the first BIC, the BIC #2 is exactly the same size as its predecessor. There are, however, a couple of subtle differences on the outside, but the biggest one is hidden from view, which is the inner mechanism, this time ten times more complex than the first - At least that's my interpretation. First, the appearance: The more apparent difference is the location of the hole where the ball exits, which sits closer to the edge instead of the center. The other, more subtle, difference is the number of lines found at both ends on the side of the cylinder, where the BIC #2 is sporting two pairs of lines while the first BIC had only one at each end.

Now, the most important difference between the two BICs lies in the mechanism itself, and here is where everything gets complicated. The goal is basically the same on the two puzzles: find the correct sequence of moves that enables you to remove the small ball bearing trapped inside. The way you do that, however, couldn't be more distinct between the two puzzles.

The only thing similar between the two mechanisms is how you go about solving them. Since the mechanism is hidden and you get very little information just by peering down the exit hole, the only way to get a clue on what's going on inside relies solely on your hearing. That was enough to solve the first puzzle, but here, I'm having difficulty not to throw 'guessing' and 'luck' into the mix. So far, neither one seems to be on my side. I've had this puzzle for the last couple of months and I've lost count of how many hours I lost trying to discover its solution. Not even a lucky solve...

What still has me confused after all this time is the fact that you can actually see a small part of the mechanism through the exit hole. Besides the large ball bearing that's visible at all times and only moves back and forth in one direction, you can also see that small part sliding in the same direction directly below the ball, but I haven't found out what exactly is its use. Since the large ball bearing isn't going anywhere and it's too large to exit through the hole, there should be another ball bearing inside, a smaller one. In fact, you can easily hear it moving inside the cylinder, but it only moves from one end to the other without coming into the exit path where the larger ball is. That's actually another problem you need to worry about once you manage to get the small ball bearing visible, as you might get it behind the large one, which is blocking its exit. I still haven't managed to do that, let alone solve it. I could've asked Jerry for some tips by now, but in doing so I would be admitting defeat, and I'm not giving up on it...yet... We'll see how far my patience gets.

Closing Comments:

Despite not being able to solve Jerry's BIC #2 in time for the review - I could've simply waited until I had it solved, but that could take months - I can still appreciate it for the complexity achieved and the improvement from the first design. As for what's next, I can only imagine how Jerry will improve on his previous ideas.

Availability: BIC #2 is currently sold out, but you can contact Jerry through his profile page and be added to his waiting list for the next batch.

Straight Arrow is ThinkFun's version of an older puzzle, the Rectangular Jam, designed by Hirokazu Iwasawa and presented at the 25th IPP Design Competition in 2005, which ended up winning the Honorable Mention award.

The original version was made from wood, but ThinkFun, as usual in their puzzles, made it using bright colors and plastic. The end result is arguable, depending on your taste, but the essence of the puzzle remains the same - A fantastic puzzle. Straight Arrow belongs to ThinkFun's a-ha! series, which present several challenging puzzles at quite an affordable price. They're quite small, but don't judge them by their size. These will make you think.

The goal of the puzzle is simple: There are three identical planks and a green arrow. The starting position shows all rectangular pieces perpendicular to the exit. All you need to do is to find the correct sequence of moves, without removing or lifting the red pieces, and be able to slide the green arrow out of the tray. Only a few moves are necessary, but they're not at all intuitive, so you're gonna need to think outside the box to solve this one.

Before you even move any piece you should already have an idea of what you're supposed to do. If the pieces are arranged in a different orientation from the one you need, then all or some of the pieces should be rearranged to accommodate the desired orientation for the green arrow. How you'll be doing that is a whole other matter, and I won't spoil the solution for you. When you finally discover the solution you'll definitely have an "a-ha" moment. This is classified as a level 3/4, and I reckon is pretty accurate. It took me about 10 minutes to solve.

Closing Comments:

ThinkFun's Straight Arrow is a very creative challenge for anyone. It's not too difficult, but nonetheless challenging and rewarding once solved. It's also worth taking a look at other puzzles in the a-ha! series.

Availability: You can get a copy of the Straight Arrow puzzle at PuzzlesdeIngenio.com. Worldwide shipping available.

Jean Claude Constantin is best known for his original designs and concepts, having made hundreds of different puzzles, but he can also take on a classic and give it his personal touch. That's exactly what he did to one of the best known binary puzzles of all time, the Tower of Hanoi or Turm von Hanoi in German.

The Tower of Hanoi originated over 130 years ago by the hand of Édouard Lucas and since then there have been so many variations it's almost impossible to count them all. I've always been fascinated by the sheer brilliance of this puzzle, so whenever I see a cool version I have this urge to add it to my collection. The Constantin version is now my third.

If you're unfamiliar with the concept, it's very simple: You have a base with three rods and a specific number of disks (the number of disks varies and with it so its difficulty); The starting position can be any of the three rods. The goal is to move all disks to one of the other two rods by obeying a simple set of rules: You may only move one disk at a time; You can't place a disk on top of a smaller one. The concept is straightforward and very easy to solve if you start with just a few disks, but for each additional disk the difficulty level rises exponentially. To calculate the number of moves you just have to apply a simple formula - 2ⁿ - 1, where n is the number of disks. Since this Constantin version has 8 disks, the minimum number of moves is 255, which is already quite challenging but still not the hardest one around.

What made me get this particular version was the colorful appearance of the puzzle itself. Constantin always excels at this with his puzzles, using many different wood tones creating a beautiful palette. The Turm von Hanoi has four different colors alternating in two groups. Also, each disk is carefully cut in the shape of an octagon - It's an eight-themed puzzle. The top of the pyramid is decorated with an hexagon to keep the disks in place. The size is average, measuring about 22cm x 7cm (8.7" x 2.8").

From the three versions I have, one has seven disks and the other two eight, including this one. Applying the above formula for the first it gives a total number of 127 moves. I'd say its difficulty level is about 6/10. The Turm von Hanoi, on the other hand, has twice the moves to be solved. While I don't consider this an extreme challenge, as classified by PuzzleMaster (level 10/10), It's still not a walk in the park. I'd put it at a level 8/10. With nine disks I might agree with a level 10.

The key to solve it is pure concentration. The solving process is the same whether you're solving a three-disk tower or an eight-disk one. You just need much more concentration so you don't lose your train of thought, which I did for a couple of times. Solving time was about 15 minutes, but with training you should be able to cut it down by half or even less. It's a very fun puzzle to solve anytime.

Closing Comments:

Liking a particular puzzle is dangerous, especially when you own a large collection. If you stick to unique concepts you'll be fine, but if you're like me, every time you see a cool new version of a puzzle you'll understand the feeling of "I must have it!". The Turm von Hanoi by Constantin is definitely a must-have.

Availability: You can get a copy of the Turm von Hanoi at PuzzleMaster for $26 CAD. For other puzzles from Constantin, click here.

Links:

Jean Claude Constantin - Official Website

Jean Claude Constantin at Puzzle Place

A Minotaurus has always been an intimidating mythological creature, but since they're not real there's nothing to worry about, right? Well, Siebenstein-Spiele's Minotaurus puzzle is very real and quite intimidating as well, so be prepared for an herculean fight with this beast. It was invented by Jürgen Reiche, who designs all wooden puzzles manufactured by Siebenstein.

Minotaurus is a sequential movement puzzle with two distinct mazes, and you navigate with two screws through them from one position to another. The puzzle is superbly built with two wood colors, mostly just to distinguish them apart, and has a sliding mechanism that moves left and right. The size of the puzzle is satisfying enough for a comfortable play, measuring 14.8cm x 8.7cm. You have to be constantly moving the two screws around to prevent your moves from being blocked.

You start with the two screws in the bottom right part of the mazes. The starting positions are also marked in the top maze, so it's very easy to get started. As you try to move one screw around you'll notice that many of the movements will be blocked by the other. The trick is to alternate between them and make one movement at a time, always trying to anticipate where each screw needs to go in order for the other one to get where you want it.

The design reminds me a lot of Jean Claude Constantin's Two Keys puzzle. The difference is that the Two Keys had just one screw and the two mazes were smaller, but the concept and mechanism is very similar. I see the Minotaurus as an advanced version of Two Keys, for more experienced puzzlers.

There are lots of dead ends and you'll feel a bit lost sometimes, but try to focus on the bottom maze and plan your route as best as you can. Treat those two screws as a team working for the same objective: reach position B, on the left end of both mazes.

The difficulty of the Minotaurus puzzle is as tough as you'd expect a sequential puzzle to be. It's rated as a level 6/7 on the manufacturer scale and, to be honest, I wouldn't be so surprised if this one was actually a level 7/7. On my first attempt it took me about 15/20 minutes to solve it, with lots of backtracking. I was able to cut it short to a little over 5 minutes on subsequent tries, but it wasn't easy, since there are a lot of movements and knowing them by heart is a monumental task. I still haven't learned all the exact movements, but I know have a better idea on where to place the screws at key moments and the route is less random as the first times.

Closing Comments:

The Minotaurus is certainly an intimidating puzzle and it's not for everyone. If you feel courageous and capable of tackling the most challenging puzzles, then this is the right one for you. On the other hand, if you're easily frustrated by an extremely difficult puzzle, I'd recommend you try something a little less complex. Note that Siebenstein-Spiele also has much easier puzzles on their catalog.

Availability: The Minotaurus puzzle is available at Sloyd.fi for €17.50. You can also buy the larger version, with balls instead of screws, for €25.80.