Sunday 19 June 2022

Qiyi Clover Pyraminx - Looks Fearsome But...

The Old Up-Up-Down-Down Works a Treat!

The Clover Pyraminx
An edge turning tetrahedron
This might be even more incoherent than my usual drivel. I have actually managed to have some time off and went to Edinburgh to visit some friends as well as relax and visit the Outlaws. A very nice relaxing time in all and a few very nice expensive meals as well. I have just arrived back home having driven 250 miles and am trying not to disappoint all you suckers lovely people who, for some reason, keep reading my rubbish. 

I had bought a few new twisty puzzles some weeks ago to try and catch up with the backlog of new toys that have come out and are being shown off by the return of Rline to YouTube. Amongst them was this Clover Pyraminx, a tetrahedral version of the edge turning Clover puzzles I have reviewed before.

I love edge turning twisty puzzles for several reasons...primarily because a lot of the solve process for them tends to be very intuitive right up to the very end game and also because they shapeshift and jumble, taking parts out of their natural orbits and often leaving all sorts of fearsome looking "sticky-out bits".
After just 4 moves!
Having seen the frightening shapeshifting, I quickly went back to the beginning and did my usual first approach for these and attempted a non-shapeshifting scramble using entirely 180º turns. It is a lovely turner but you do need to watch your thumbnails as the edges get caught and attempt to rip your nails off (YeeeeOuch!). It doesn't take long to get a nice mixed up puzzle and as expected the solve is a pleasant logical one of performing 3-cycles on the petals until they are all in place again. To you non-twisty puzzlers it sounds impossible but it really is just pure logic. The first 2 times that I did this, I magically ended up with an easily fully solved puzzle after just doing my logic solve process. At this point, my luck ran out because the centre triangles were scrambled when I had finished. For some silly reason I had just thought that solving the petals was just automatically solving the centres at the same time. As has been said by almost all puzzlers around the world: "you are not terribly bright sometimes"!

Oops! Now what?
I sat and stared at this for quite some time with absolutely no clue how to control the centres without mucking up the petals. In desperation I descrambled and resolved and from now on every single time left me with 3 centres swapped around. Not always the same ones but always three of them. It was time to Think©. I use the copyright symbol even if Allard cannot/won't do twisties because I know that if he really tried then he could easily do them. After some fiddling with the Up-Up-Down-Down combination for a while I had a Eureka moment (No, I did not make Mrs S sick by running around naked). A simple set of 4 moves moves 3 petals and leaves one centre piece from one face on an otherwise untouched 3rd edge. If I turn the third edge and undo the original 4 moves then I reverse all the petal moves but have created a 3-cycle of the centres. It is a COMMUTATOR and I found it all by myself - I am a genius! Ok, maybe not (that term refers to Derek) but having found my little set of moves I was now able to solve the simple scramble every time - Yay! Time to take the next step and do a full jumbling and shapeshifting scramble:

Oh dear! That wasn't a good idea!
Yet again I nearly lost my thumbnails and suddenly wished that I hadn't done that! The usual first stage is to return it to the original shape (it always leaves you with pieces out of orbit but you can sort that later). The process of returning to tetrahedron had me stumped again for quite some time. My first time I managed to almost do it before realising that every single edge was perpendicular to the correct orientation and I had created an unsolvable position. I corrected that and tried again. Each time I could get almost there but was always left with a protrusion (not bad for a man my age!) and yet again I had to think© - luckily for me the thinking© did not have to be deep. If I do my Up-Up-Down Down moves with a partial edge turn and it sinks the protrusions back inside...Mostly!

Where did that come from?
I managed to get it back to tetrahedral shape except there were black pointy bits sticking out and it was not terribly obvious where they had come from. They had no stickers on them and therefore were obviously internal pieces that had been left outside during scrambling and partial solving. Where did they belong? The clue to that came from looking at where they always appeared. They were always found in the place of the centres and I could eventually (after banging my head on the wall for a bit) workout that the centres were now inside the puzzle.

If you twist some of the edges until you find a little clue:
The centre is hidden in a little cavity inside the corner - in the picture to the left the red triangle is inside the puzzle and only revealed by partially turning an edge. So, how to I swap those? On various occasions, I have managed to get anything from one to 3 separate sticky-out bits on various faces. The secret to beat it? Yes, you are good at these! It is the Up-Up-Down-Down moves again. This time you need to do it with 2 edges hard turned out of place and then performing our magic sequence which returns the puzzle to proper shape. Phew! That wasn't too bad was it? Actually, it nearly killed me - all of these discoveries were over a period of 10-14 days and had my colleagues at work laughing at me when I either swore at the bloody thing for having protrusions or swore at it for injuring me. I really suffer for you guys, you know!

Once I had my shape again, I was able to do my intuitive solve using the magic sequence. This, I knew would only get me so far as some pieces will inevitably shifted out of their natural orbits and would not have been returned by the removing of the shapeshifting. Eventually, I ended up with something like this (sometimes on several faces)

Nearly solved but 2 petals are out of orbit (ignore the centres)
With the Curvy copter or related Clover cube (both cubic edge turners), this sort of issue is sorted by carrying out double jumbling moves to swap orbits until they are back in the correct orbit and then can be moved into place by intuition. There aren't enough faces to do that here and I had to adapt the magic technique to allow the fix to happen. Again we have a 3-cycle of pieces using the simple 4 move sequence but starting with a partially turned edge:

Turn one edge and then cycle those petals
Using the front left and right edges and starting with the left one, I can do a Down-Down-Up-Up and those 3 petals cycle around until they are correctly placed. After that is done with all the orbit errors, then the centres may need to be solved and you are done! Fantastic! I worked it out all by myself with only a little (alright, a LOT) of help from Allard. My colleagues were amazed and everyone thought I was brilliant.

And then I tried to do it a few more times and found something awful:

It's a 2-cycle! That's impossible!
My colleagues laughed at the look of horror on my face when I came up with this scenario. I had just 2 centres swapped and as any twisty puzzler knows, a 2-cycle is against the "law of the cube". This is just impossible. 

After my initial blank thoughts, I went back to some of my early blog posts and realised that I had an error caused by a "False equivocation". This occurs when you place a piece into position because it looks like it should go there but in reality it is out of place. This can occur either because it looks identical to some other piece or because it has no stickers to tell you where it belongs (this was the case here). I realised that I had put the blank sticky out bits back inside the puzzle but they were placed randomly into whatever vertex I found. I realised that I had inadvertently swapped 2 of this blank internal pieces with each other and had no way of knowing. The manifestation on the outside was a pair of swapped pieces but in reality it was 2 pairs of swapped pieces and this is perfectly possible and relatively easy to fix. I used my earlier fancy move to take a vertex out and swap it with a centre and then replace it with a different vertex before putting the second one back where the first had been. This invariably left me with a 3cycle of centres to do and my puzzle was done. Hooray!

This is actually a wonderful puzzle - it is not too difficult for any experienced twisty puzzler and has some interesting features to make it a must-have in the collection. I would also say that anyone who is just starting out on twisty puzzles should also obtain a copy - solve the Clover cube or Curvy copter first and then move onto this one. It takes you several steps further in your solving and learning process without being too frustrating. Just watch out for those thumbnails! It is available from most good puzzle stores - PuzzleMaster have it here, or you could try the Hong Kong stores. Well worth your money!


3 comments:

  1. I’ve had 2 of these puzzles and freaked out when the hidden inside pieces emerged. On both of my copies, the thing fell apart and I was unable to reassemble. (A student of mine broke the second one. I warned her too!) I’ll be getting yet another one.

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  2. If you think of this one as a mastermorphix with a few hidden corners, you'll realize it's just a 3x3 and can be solved as such. It's quite deceptive.

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    1. I will need to have a second look at it! It really never occured to me that it was a 3x3

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