An Advanced 12 Color Megaminx Solution

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A 12 Color Megaminx Solution
By Daniel Hayes
This guide is not your typical beginners guide, and I will therefore make a few
assumptions. For example, I assume you know how to solve a 3x3x3 Rubik’s cube.
Furthermore, I assume you have played around with a megaminx and have the gist of
how things move. Many of the details up until the last layer will be left out, as they are
nearly identical to using the Fridrich F2L on a normal cube.
Without further ado, let’s get started.
1.1
The Color Scheme
I’ll try to share with you the color scheme I use, since there is no official standard. It is
important to get a feel for which pieces are where each face is relative to others for when
I describe the order I solve the faces.
So here’s how it’s set up
Dark green, gray, red, yellow and pink go clockwise around the light green.
Blue, black, brown, white, purple and orange are opposite those colors in that order.
A picture should help:
1.2
Notation
On a puzzle with this many sides, notation is kind of tough. Here is my attempt at
labeling the faces of a megaminx:
Hidden from view completely is the B face (Orange).
Luckily, I shouldn’t have to use the LUL and RUR faces in this guide, but I will have to
use a few doubled-letter faces. Taking a tip from Grant Tregay’s notation scheme,
algorithms will be written with a “/” in between face labels, in an attempt to avoid
confusion.
To denote a 1/5 clockwise turn of a face, I will simply use that face’s letter. So F would
denote a 1/5 clockwise turn of the F face. F2 would denote a 2/5 clockwise turn of the F
face. F’ denotes a 1/5 anti-clockwise turn and F” denotes a 2/5 anti-clockwise turn.
2.1
F2L
It should be noted that I always solve the colors in the same order; this helps because I
only have to look for a specific color at a specific time. It cuts down recognition time
greatly.
The first step is analogous to the F2L on a regular 3x3x3 Cube. The first step is
to make a star:
And then place the corner-edge pairs:
The CE Pairs are simple enough using normal F2L algorithms, though some need to be
slightly modified. In fact, at this point there is so much room on the puzzle that you can
pair the corners and edges intuitively before slipping them into place.
I use bright green as my starting color because it is easiest to pick out. And with this
many colors on a puzzle, you need one that stands out so your inspection time can be well
used.
2.2
Completing a Second Face
At this point it is best to pick another bright color. I go with the red face. The goal is to
first place the two remaining edges of one of the semi-complete faces:
After that, place those CE pairs to complete that face. There is still enough room to
efficiently pair the pieces before slipping them into place without using actual algorithms,
though if the opportunity lends itself, some of the algorithms can be much faster.
2.3
Completing a Third Face
At this point you can choose either face which touches both complete faces to work on.
On my minx, I go with the yellow. You only have to place one edge, so recognition is
very quick:
Again, place the CE pairs that complete the face. At this point space is getting tight, so
you may want to stick with algorithms to place them.
2.4
Completing the Fourth Face
At this point, any of the three totally incomplete faces is fair game. In all three cases, you
again only have to place 1 edge. I choose orange on my minx:
Here it is best to just use the algorithms you know from the cube to get the CE pairs done.
3.1
Second to Last Face OEE
The aim here is to get a grouping of corners and edges on one of the two remaining faces,
like this:
The above positioning is optimal, but not necessary.
The first step in getting here is to orient those two edges. There are really only two cases:
one oriented correctly, and none oriented correctly:
R / F / R’
R / F” / R’ / D’
Both of these can have the pieces reversed, in which case the setup and execution of
algorithms should be reflected horizontally across the picture. This is not necessary, but
sets up the next step a little better.
3.2
Second to Last Face CEE Triplet
Here, we’re trying to place the corner piece that matches the two edges we just oriented:
There are no real algorithms for this step, it’s sort of intuition. The first step I do is to try
to get it to look like this, or its mirror image:
From here, a simple F / D’ / F’ / D / F2 should fix you right up.
3.3
Completing the Second to Last Face
Simply place the last two CE pairs as you have been all along, this is nearly identical to
solving two CE pairs on a cube.
4.1
OLLE
Here’s where the meat of the solution lies. Everything before this point in the solve
(other than the order) can be done with little help if you’re familiar with a cube. This
step is also similar to the cube, and the same algs will work with some minor
adjustments. There are only three ways the edges can be oriented:
 = D / F / R / F’ / R ‘ / D’
 = D / R / F / R’ / F’ / D’
 / F2 / 
4.2
PLLE
Here, we just want to get the edges in their correct places relative to each other. There
are three incorrect situations, and the first two have inverses:
R’ / F’ / R / F’ / R’ / F2 / R
R’ / F’ / R / F” / R’ / F” / R
UR’ / F’ / UR / F’ / UR’ / F / UR / F” / UR’ / F” / UR
What we are doing here is pretty much a “working edge” system. Knock an incorrect
edge out of the way, position the F layer, replace the edge, and so on. Also notice that
the third algorithm is really just a slightly tweaked combination of the first two.
4.3
OLLC
This step gives quite a few folks some problems. Generally the idea is the same as on a
3-cube, but the finer details can be slightly tougher to work out. There are fully thirteen
different incorrect cases, many of which have non-trivial reflections. I will include some
important reflections, but omit most.
 = R’ / F / L / F’ / R / F / L’
 = L / F’ / R’ / F / L’ / F’ / R
 = D’ / L’ / UL’ / UR / UL / L / D /
 = D / R / UR / UL’ / UR’ / R’ / D’ /
UL’ / UR’ / UL
UR / UL / UR’
Everyone should thank Grant Tregay for those two algs, before he showed them to me, I
had no way of efficiently dealing with those cases!
 = R / UR / UL’ / UR’ / R’ / UR / UL / UR’
R” / DR’ / R / F’ / R’ / DR / R / F / R
 = R” / DR’ / R / F2 / R’ / DR / R / F” / R
R” / DR’ / R / F” / R’ / DR / R / F2 / R
(It’s worth noticing that those last three are essentially identical.)
F’ / 





F2 / 
F” / 












F / 
 



/F/



 / 

Generally, with the 4 and 5 incorrectly twisted edges, there are many different ways to do
them, and I’ve only offered one. Most of them are just combinations of two of the two
incorrect corner cases and applying one of those algorithms will get you to a workable
state.
4.4
PLLC
Finally! The last step! And luckily it’s not nearly as lengthy as the previous one. There
are a whole bunch of different cases for the PLLC, but every last one of them is done the
same way. The only time the method needs to be tweaked at all is when you have four
corners that need swapping. We’ll save those for last.
I will create two algorithms to keep from having to type so dang much in this section:
 = R’ / DR’ / R and  = R’ / DR / R
 / F /  / F” /  / F / 

/ F” / / F” / / F’ / 
All cases where three corners are incorrect can be generalized to the above two or their
inverses.
In general, we are removing corner X by doing , then positioning the corner occupying
the space that X belongs in is moved to FDR by twists of F. is then performed, and the
process repeats until you run out of incorrect corners.
This method works perfectly fine for the cases where all 5 corners are wrong too:
(There may be more of these, but I don’t want to hunt for them and they’re all handled
the same way)
However, a slight adjustment is needed for the 4 incorrect edge cases:
 / F’ /  / F /  / F” /  / F” /  / F2 /  / F2
 / F” /  / F2 /  / F’ /  / F2 /  / F” /  / F
The difference here is that after you place the first two corners, you do not have an X corner that belongs in
the F layer. So instead you move an incorrect corner out of the F layer, and then proceed as before.
Congratulations! You should have a fully solved Megaminx!
5.1
Notes
I hope I have been thorough and clear enough to provide some aid to those wishing to
quickly solve the Megaminx. Some of the corner permutations may have been left out
because I feel that the method is so similar in every case that no algorithm is needed, and
they’re a pain to hunt for. I do think I managed to get all of the corner orientations
though. If you find one that’s missing, let me know!
The pictures were obtained by taking a screen shot of the Virtual Megaminx
(http://www.geocities.com/hua_jz/megaminx.html ) and editing the heck out of it in
Photoshop.
The algorithms I use were found independently (except where noted), yet most are so
obvious I can hardly claim them as my own. If you see something you think you deserve
credit for, by all means let me know! And thanks to Dennis Nilsson for helping spot
some incorrect algorithms.
See Grant Tregay’s Solution at
http://grant.tregay.net/cube/solutions/megaminx/index.html
Questions? Comments? Kudos? Disparagement?
Send them to Swedishlf@hotmail.com
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