# Mirrored Inverse Sexy Method (MirIS)



## Cride5 (Jul 7, 2016)

A beginner method optimised for speed and simplicity

EDIT: Full tutorial here.

Rationale


Spoiler



A while back - while trying to find the easiest possible beginner method I came up with SAM (the Single Algorithm Method).

Since then I've been teaching it (and variants of it) to a number of people, sometimes even in a foreign language. While most people seem to be able to grasp it after a while, I've found it has a number of issues:

Solving middle layer edges (despite being only 3 moves) turned out to be difficult to explain, mainly because the edge needs to NOT be aligned with its centre before doing the 3-move sequence. I also found that users were often confused about which side to turn in the 3-move sequence.
Solving orientation and permutation simultaneously in the top cross, while an elegant solution seems too much intuition for many absolute beginners. This is where a lot of them mess up and have to go to a previous step.
The process of solving the last edge on the top cross was probably made more difficult by sticking to a single alg, and I ended up teaching people just to use R U R' U R U R'
On last 5 corners users are tempted to turn the top layer since they were used to doing this while solving the first 3 on the bottom. I used to avoid this by teaching a variant which simply solves all the edges first, then all 8 corners last. This reduced the number of concepts but lead some horrible situations where the cube needs to be inverted multiple times.
Users often forget the last move in the 1-2-3-4 sequence because the goal (of placing the corner) is competed after 3. A little bit like the problem with ATMs that give you your cash before returning the card.

In general, I think focusing strictly on just one algorithm was detrimental to the ultimate goal of making it easier for beginners. However, I still feel that a good beginner method should minimise the number of algs, and number of moves in each alg, while avoiding making too much use of intuitive solving.



Steps

Cross

3x corner-edge pairs

Top cross orientation

Top cross permutation

Last 5 corners

Details

For this method the Inverse Sexy move (U R U' R') and its mirror (U' L' U L) are used.

We also assume that the user is starting with the white cross.

IS = 'Inverse Sexy'
MirIS = 'Mirrored Inverse Sexy'
C+E = 'Corner+Edge'


*1. Cross*
Intuitive. Use daisy if absolute beginner.

*2. 3x corner edge pairs
2a * Look for a corner in the top layer, place it above its 'slot'
*2b * If the white sticker is on the top layer apply IS x2
*2c * Hold the cube so that the white sticker is facing you. If the corner piece is now on the left then apply MirIS, otherwise IS
*2d * Look for the adjoining slot edge in the top layer
*2e * Rotate the top layer so that its side lines up with its center
*2f * Hold the cube so that the edge is facing you, if the slot is on the left apply MirIS, otherwise IS
*2g * There should now be a C+E pair above the slot. Repeat 2c to insert the C+E pair

If you're looking for any pieces not in the top layer, find the slot with the piece and apply IS.

*3. Top Cross Orientation
3a* Look at the edge in the last unsolved slot, hold the cube so that its yellow sticker is facing you
*3b*
- If the slot is now on your right:
Rotate any top layer edge without a yellow sticker facing up into right side and apply IS​- If the slot is now on your left:
Rotate any top layer edge without a yellow sticker facing up into left side and apply MirIS​Repeat 3a/3b until all edges in the top layer are oriented.

*4. Top Cross Permutation*
Attempt to align the cross pieces with their sides, if they can't be aligned then there are two cases:
*4a* Two adjacent pieces can be can be aligned: Rotate the top layer so that the two pieces are in the back-left corner and apply IS, then repeat step 3b
*4b* Two opposite pieces can be aligned: Apply IS, then step 3b, then step 4a

*5. Last 5 Corners*
As documented in 8355 or SAM, only using Inverse Sexy instead of plain Sexy Move


Advantages over SAM

C+E pair insertion has easy transition to CFOP and avoids adding another concept for separate insertion.
A small number of simple principles are used consistently throughout such as, "orient white/yellow sticker to face you", "place the unsolved edge into the R/L"
Inverse Sexy is more beautiful than Sexy ;-)


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## obelisk477 (Jul 7, 2016)

What kind of times can *you*, specifically, get with this method? Just curious


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## Petro Leum (Jul 7, 2016)

IF i organise a cubing course at my university next semester, i will be using this.


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## bobthegiraffemonkey (Jul 7, 2016)

Didn't realise you were still around, nice to see you post. Interesting method and you've clearly thought it through well, I'll probably try teaching it some time.


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## Cride5 (Jul 8, 2016)

obelisk477 said:


> What kind of times can *you*, specifically, get with this method? Just curious


37.38, 37.58, (50.44), 44.48, (35.36) = *39.81*
I'm sure an experienced CFOPer with good turn speed would be able to do much better. Fancy a try?



bobthegiraffemonkey said:


> Didn't realise you were still around, nice to see you post. Interesting method and you've clearly thought it through well, I'll probably try teaching it some time.


Hi Mat, sure has been a while. Busy as always but I try to pop in from time to time. Let me know how the teaching goes.


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## Cride5 (Jul 10, 2016)

I've put together a full tutorial for beginners, available here.


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## bobthegiraffemonkey (Jul 10, 2016)

There's some missing awkward cases which might confuse people, otherwise pretty nice tutorial and I've bookmarked it for reference .

-For c-e pairs, doesn't mention the edge being in the wrong slot
-For top cross orientation, doesn't mention if all the yellow edges are in U but not oriented
-For L5C, there's a few awkward cases missed, here's an example which I think includes them all (also diagrams have yellow on top instead of white):


Spoiler



scramble: U R S U S' R' S U' S' U' z2 y'

D IS
URF is white so guide says do IS, but need to put unsolved corner at DFR first

D IS D IS*3 D' IS*3
no unsolved corner to put at DFR before fixing stuff

IS*4 D2
can't put both corners on D by rotating

D2 z IS*4 D IS*2 D' L2


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## Cride5 (Jul 11, 2016)

Thanks for the pointers. I've updated the tutorial to fix these issues, and also added some more explanation of the steps.


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## Cride5 (Jul 22, 2016)

Tips for improving speed/efficiency and transition to speed solving

These steps are roughly ordered by difficulty:


Improve speed/efficiency when solving C+E pairs:
- When lifting a corner from an incorrect slot to the top layer, turn cube so that the white sticker is facing you and apply IS/MirIS to place the corner into the top layer without the white sticker facing up.
- If lifting a corner from an incorrect slot and its white sticker is facing down, place its adjoining edge in the top layer so that its side sticker is in the same face as the matching corner sticker, then apply MirIS/IS to lift the corner and create the pair simultaneously.
- If lifting a corner from an incorrect slot and its white sticker is not facing down, and the top sticker of its adjoining edge matches the other side sticker of the corner, rotate the cube so the white sticker is facing you, and place the adjoining edge in the back of the top layer. Apply MirIS/IS to lift the corner and create the pair simultaneously.
- When a corner has its white sticker facing up, instead of ISx3, rotate the cube so that the corner sticker that matches its adjoining edge's side sticker is facing you, then apply MirIS/IS and use the technique above to create the C+E pair on the next application of MirIS/IS.
- If a corner with a white sticker facing up is already joined to its edge, instead of ISx3, simply lift the C+E pair into the top layer with R U' R'.
- Learn to recognise the R U R' (or L' U' L) insertion case. The corner is in the top layer with white facing to the side, the edge is in the back of the top layer and the top stickers of the corner and its edge are not matching.
- Once a corner is placed in its slot, a faster pairing/insertion can be done by placing the edge in the back of the top layer and applying: F' R U R' U' R' F R or its mirror F L' U' L U L F' L'
Switch from Daisy to solving the full white cross from the beginning.

Improve speed/efficiency when solving last 5-corners by:
- using the regular sexy move (R U R' U') to place corners that would require 5 repetitions of Inverse Sexy.
- ensuring that when pieces are moved from D to U, the yellow sticker is not on top by choosing the correct alg (Sexy or Inverse Sexy)
- avoiding cases that require 3-repetitions by preferring to move pieces already in D up to U using the technique above.
- Solving orientation of corners with the correct alg (Sexy to twist clockwise, Inverse for anticlockwise).
Solve top cross in one step by solving orientation and permutation simultaneously, as explained here.

Reduce pauses between steps by looking for the next piece(s) while solving the current step.
Learn to solve the white cross blindfolded so that the moves for solving it can be planned during inspection.
Learn how to solve the C+E pairs intuitively - tutorial here.
Fill in the 4th slot and learn to solve the last layer with algorithms.

At this point you will now be using basic CFOP method, but you may wish to investigate other methods such as Roux or ZZ to explore other concepts and find which style suits you best.


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## Whurm (Oct 25, 2016)

There is an error, in either this algorithm or the one on your website(http://cube.crider.co.uk/miris.html).

2b here says 2x while on the other site it says 3x.


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## Cride5 (Oct 26, 2016)

The tutorial on the site has been more carefully authored so I recommend following that one.

If the steps here are followed as a sequence the step 2c still works. It sets up the corner so that the white sticker is not on top, making it solvable in the next step (2c).


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## Whurm (Nov 22, 2016)

So far I'm loving this method. I've taught it to over 20 people in the nursing home where I volunteer. They LOVE it. Being able to solve it brings a smile to their faces. 

They only problem I'm having is at the very end if the two last spots are diagonally opposite. For some reason everyone keeps messing up here. If it happens we usually start over. Any hints or ideas? Detailed steps would be great. After the half turn do you just solve the right bottom right corner using IS, then turn the bottom layer to solve the second? Do you every half turn back?


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## Cride5 (Dec 1, 2016)

Hi Whurm, great work volunteering at the nursing home - I'm sure they really appreciate it.

The alignment step is probably the most difficult to understand conceptually, since (in the adjacent case) you have to understand exactly _which_ two edges are permuted correctly. For those familiar with the cube's colour scheme this is easy, but for a beginner maybe not. The important thing here is to actually attempt to align all pieces. Go though each of the four possible U-layer positions until two of the edge pieces match their side-centers. Once these matching pieces have been identified (in the adjacent case), they must be placed in B and L positions. If they are not placed there before proceeding, then you will end up back where you started.

With the correctly permuted edges in BL, just apply IS once, and you will end up with three yellow edges on top, and one in the 'slot'. Using the same approach as the previous 'yellow cross' step, rotate the U-layer until the unsolved piece is in the R-position of the U-layer. Applying IS from here will complete the top cross.

In the case that is is possible to align two top-layer edges that are _opposite _each other, then do IS, followed by U, then IS (to fix the yellow edge again). At this stage you will have the adjacent case, and you can follow the instructions above to solve it. When you have the opposite case, the position of the U-layer doesn't matter the first time you apply IS, since any of the two opposite edges can be considered correct relative to each-other.

The tutorial read a bit like a program, requiring you to skip to previous steps. I've updated it to be more linear, so you can just follow the alignment instructions from top to bottom. I hope that makes it clearer.

If people are still struggling with this approach to doing the top layer edges, an alternative method is the one detailed here:
http://cube.crider.co.uk/beginner.php#3te


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## gateway cuber (Dec 1, 2016)

Cride5 said:


> A beginner method optimised for speed and simplicity
> 
> EDIT: Full tutorial here.
> 
> ...


learning this and if I like it, I'll master this.


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## gateway cuber (Dec 1, 2016)

what the heck this is amazing!

somebody needs to make an L5C alg set, this is like ZZ-CT adapted to cfop.


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## Silverback (Dec 1, 2016)

One suggestion for the top cross: 
Move the edge in the slot to the top with an F' or R, so its ends up with the yellow sticker next to the yellow center (forming a part of the cross). Then rotate the top layer to put a misoriented yellow edge into that position and undo that F' or R move. This puts another yellow edge to work with in the middle layer.
Repeat until you have 3 oriented yellow edges in the top layer. Don't worry about permutation.
Before you place the fourth edge, you have to check, how many of your top edges can be put into their correct positions at the same time. If you can place all three or not more than one, you have a bad case. Then keep swapping pieces until you get a good case. 
If you can place exactly two pieces, you have a good case. It doesn't matter if these edges are next to each other or opposite of each other. 
Put the third edge on top of the slot, replace it with the one in the slot, rotate the top to bring the non-yellow edge on top of the slot and move it into the slot. 
This will solve all 5 edges.
Hope this was clear. If not, I can make an example.


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## Cride5 (Mar 21, 2017)

Due to popular request I've added a 'censored' version of the tutorial that replaces the word 'sexy' with 'super'.

Get it here: http://cube.crider.co.uk/miris.html#super


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## mitja (Mar 21, 2017)

Hi. I believe this is a beautifull method to solve the cube. I teach kids regularly how to solve the cube, but i use tha regular layer by layer approach: cross, corners, 2nd layer edges, top cross, top cross perm, niklass alg for corners perm and last corners orientation. With more advanced kids I go straight to 3look OLL with cross +1-2xsune or antisune. Then 4 look PLL with A and U perm. That way I prepare them for CFOP.

My experience while teaching was:
1. The hardest is the cross. The reason is, they get to know the cube for the first time. To understand the 3D concept of solving the pieces (not the stickers colour) is hard for some of the children. It gets much easier once they move to the next stage. It also gets very easy for them to learn algs, like 2nd layer edges alg or sune, niklas alg.
If i could calculate time needed to teach them each stage, I need about 60% of the time for first 2 layers and only 40% of the time to teach them solve the rest.

What was my point? I believe this MirIS method is great, but not the complete beginners method. I would call it advanced beginners method. To understand IS move is not so easy and using kind of keyhole is also not that easy either.
Alternating between IS and inverse IS also takes some good cube awearness for a beginner.
And finally the last 5 corners are very hard for a beginner. If I wouldn't already use the simillar corner orientation and then permutation when I was first putting toogether the megaminx, I would struggle to understand it.
I think it is very nice with adult beginners, especially someone that gets scared of algs. I very much remember reactons by lots of my friends when they say:" Doing this cube is just memorising hundreds of algs. It is very boring."
They are always surprised once I show them that two thirds of the cube is done with pure intuition and never repeated twice.

Anyway, it is very tempting method and I will try it with beginners to compare how they will cope with it.


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## Le Zouave (Jan 8, 2018)

Hi, I just received my first cube 5 days ago and I must say that your method is brillant. I was scared to learn a handful of algorithms but this one only have two. The most challenging was to understand why I musn't move the 2 upper layer while doing the 3 yellow corners but I must say that I'm a vertical reader.
Once I understood what part where affected by IS and MirIS and that repeating 6 times the same algs return to the original state, it's very easy.


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## BirdOfChaos (Oct 29, 2018)

I love this method. Thank you very much Cride5! 

I used to know how to solve layer by layer a long time ago, but have long since forgotten any of the algorithms. I recently came back to cubing and I didn't want to memorize too many algs before being able to solve the cube. I was able to teach myself how to solve the cube again with the MirIS method in less than an hour. Quickly my times decreased from about 15 minutes (when I still needed to read the instructions once in a while) to 3, and now I can solve in about 1m 1/2. One trick that I quickly realized I needed was to make sure that the correct edge piece for the F2L step was not in the middle layer when bringing a corner down to the white layer, or if it was, to select that slot to bring down the corner to, so that the edge would be displaced to the top, ready to use. Otherwise I'd need another separate IS move right after to bring it to the top.

My goal is to get below 1 minute, which I never achieved even back in the 90's. For that I'm looking at the tips for improving that you have listed. I find that some of the tips are clear, but for some others (like the very first one for example), I'm not sure what you mean and during which step it's supposed to be done. I think that a follow-up page with instructions on how to progressively get from MirIS to 2-look CFOP would be super useful for those of us who have "mastered" MirIS. I'm going to time myself during the various phases of the MirIS to see where I need to improve most and start there.


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## Cride5 (Oct 29, 2018)

Hi BirdOfChaos, welcome to SpeedSolving community.

Glad you managed to get back into cubing with MirIS.

The '3 slots' step of MirIS is basically a restricted version of the F2L step in CFOP. If you use the technique to fill up 4 slots instead of 3 you are onto a normal CFOP last layer.

To progress from MirIS to CFOP I'd recommend doing the following:
1. Combining daisy and cross into a single step
2. Filling the 4th slot and learning learning 4-look last layer
3. Learning shorter sequences for inserting corner/edge pairs during F2L, start by looking for tutorials on intuitive F2L
4. Progressing onto 3-look and then 2-look last layer


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## BirdOfChaos (Oct 30, 2018)

Thanks Cride5!


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## Skip (Feb 10, 2019)

First of all, thank you for developing this method and tutorial. It's easy to remember once you understand it.

After several hour of missteps, I finally got the algorithm to work! And I think I finally understand it. There were a few places where I had difficulty: In building the F2L, the tutorial says "Now hold the cube so that the edge is facing you." It think it would be better to have said "Now hold the cube with the vertical stripe facing you." I held the cube at 45 degrees and left and right of the edge were not clear.

A second point of confusion concerned building the yellow cross when the edge wasn't in the keyhole. In one case it was in the middle layer back right, ind doing IS did not budge it. I wound up moving the keyhole and things worked OK after that.

My final Ah-Ha was realizing during the solution of the five corners, that the two non-yellow corners needed to match the two center (and bottom tiles) on the faces that met at the corner. Not only that, but the tile was properly positioned when the tile matched the color of the tile to its left. When positioned correctly, a new bottom corner can be chosen: if the top tile has a yellow face, match the bottom corner to the tile and move it into place; if the tile on top has a white face, move an unsolved corner into place and do an IS to move it to the top. Then move the matching corner into place (if necessary).


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## Rumpu-Jussi (Aug 9, 2019)

I just registered to these forums to say a big thanks to you for publishing this method!

Just last week, my daughter went through the stuff that ended up at our home some years ago when we emptied my late mother's apartment. She found two cubes in there, the other is a Rubik's brand, the other unlabelled, both from the 80s, I believe. 

When I was in my early teens, in the early 80s, my brother and I got a cube as a present for Christmas. I remember how we got hints on moves from our schoolmates, who got them from who knows where... There was no 'net then, nor the moves had any names, at least not that we knew of. We just memorised the patterns: "If these edges are like this, then do this..." The method that we used is now known as the beginner LBL, I think.

While trying to find out a simple method, without the need to memorise umpteen moves, I first stumbled on the 8355-method on the SpeedSolving Wiki. However, the instructions for the last five corners were, IMO, a bit lacking. Then I found a better description of the method on cube.crider.co.uk, and a pointer to the MirIS -method.

Now I have the MirIS page saved as a PDF on my phone, so that where ever I go with the cube, I have the method at hand, provided I have my phone with me.

Next up, I'll probably teach my daughter the MirIS method, then I'll tackle Roux, or ZZ, they seem interesting.


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