# Advanced M2 guide



## mark49152 (Nov 27, 2015)

Here are my five favourite Advanced M2 tricks. I found these scattered among many sources, so I thought it useful to collect into one place. I hope they help.

*What is Advanced M2?
*
Basic M2 solves one edge piece at a time. Advanced M2 adds some tricks for solving two pieces at a time, for shorter and faster solutions. M2 lends itself to this kind of extension very well, as this guide will show.

Many of the algorithms for solving two pieces at a time are commutators, similar to those used in 3-style edges. Sometimes people talk about “switching” to commutators. It’s important to realize that you don’t have to switch* to commutators, or switch to Advanced M2 – it’s not all or nothing. Given a sequence of letters you have memorized for a solve, you can solve some individually and some in pairs, depending on what tricks you know or like. Using basic M2 as a foundation, you can add Advanced M2 tricks at your own pace, and the more you add, the more you benefit.

This guide assumes that you are already proficient at M2, for solving one edge at a time, using the DF buffer.

(* = some people will say you should switch to using a different buffer for 3-style, for better algs, but it still doesn’t stop you adding commutators to your M2 solves for as long as you want to stick with M2.)

*1. Avoiding those nasty FU and BD algs
*
I’ve ranked these tricks by how beneficial I think they are, which roughly equates to how many moves they save. My favourites are the ones that simplify solving those nasty M slice cases.

For the BD and FU targets, I use the algs recommended by Noah in his tutorial – D M’ U R2 U’ M U R2 U’ D’ M2 and its inverse. They are as good as any I’ve seen. Solving these targets individually is perhaps the most painful part of M2. Luckily there’s a much shorter way to solve these when they come immediately before or after a non M slice target.

For example, to solve BD-FL, do M2 (U’ L’ U) M’ (U’ L U) M’. You use the usual setups for the FL sticker, but replace the usual M2 as shown. Save yourself 9 moves! This trick works for any of the non M slice targets.

Tips for remembering: If the M slice target comes first, the M2 comes first, otherwise it comes at the end. If, like me, you swap the FU/BD stickers during memo when they come second in a pair, then an easy rule of thumb is that if you memorised the FU sticker the moves are M, and if you memorised the BD sticker the moves are M’.

FU-s = M2 s M s’ M (where s/s’ are the setup/undo for the s sticker)
s-FU = M’ s M’ s’ M2
BD-s = M2 s M’ s’ M’
s-BD = M s M s’ M2

If you’re interested in how these work, they basically do an M2 set up of the buffer into the UB position, and perform a commutator to cycle UB, FU or BD, and the target sticker.

*2. Consecutive M slice targets
*
Occasionally, you don’t have the chance to combine FU or BD with an adjacent non M slice target, so it’s useful to know some tricks for combining M slice pieces as well. Here’s a nice simple one.

To solve FU-BD, do an x rotation, then do the alg for solving FU, but without the trailing M2. Likewise, to solve BD-FU, do an x rotation then the BD alg without the leading M2. These are nice and easy to remember. You can use M’/M setups if you prefer that to rotations.

FU-BD = x D M’ U R2 U’ M U R2 U’ D’ x’ (= [x D: [M’, U R2 U’]])
BD-FU = x D U R2 U’ M’ U R2 U’ M D’ x’ (= [x D: [U R2 U’, M’]])

For the UF and DB stickers, these have really nice short solutions anyway, and I have not found any really good tricks for combining these with adjacent targets, apart from the obvious cancellations like M' U2 M U2. You can of course set them both up to the UB target and use commutators, but the setups aren’t significantly shorter than the individual solutions. A couple of exceptions:-

UF-DB = M u2 M u2
DB-UF = u2 M’ u2 M’

I remember these as follows: UF-DB is like the DB alg (M U2 M U2) but with wide u turns, and likewise DB-UF is like UF. These don’t save many moves but are easy to remember.

*3. Dealing with the BU sticker
*
In basic M2, this sticker is almost as bad as FU and BD. Although it can be solved with a regular setup, the setups are a few moves long. For basic M2, I learned (B’ R B U R2 U’) M2 (U R2 U’ B’ R’ B).

First up, there’s a quicker way to solve BU individually than by using setups. Try (U M’)3 (U M) (U M’)4. It’s an alg that flips both the buffer and target pieces, followed by an M2 with cancellation. It's still a lot of moves, but you might find it faster.

Another way to solve BU is to set it up to the FU or BD positions by U2 and B2 respectively, then use one of the solutions for combining those stickers with adjacent targets. So to solve BU-FL you can do B2 M2 (U’ L’ U) M’ (U’ L U) M’ B2, or U2 M2 (U’ L’ U) M (U’ L U) M U2, whichever you prefer. That way BU only costs you 4 moves.

However, there are two things to watch out for with this approach. First, take care not to move the other sticker by your setup. For example for BU-UL you could use a B2 setup but not a U2 setup, unless you want to remember you have moved UL to the UR position. Secondly, if BU is the second sticker in your pair, you must set it up to the opposite piece on the M2 slice – so to solve FL-BU you would setup to the FU sticker but then do the solution for the BD sticker, e.g. U2 M’ (U’ L’ U) M’ (U’ L U) M2 U2

*4. Commutators on UB
*
I’ve seen this trick given the headline in at least two other Advanced M2 guides, but in my opinion it ranks below the preceding ones because typically it does not save as many moves. The principle behind this trick is that if you do a basic M2 solution for a non-M slice target, followed by an M2 to solve UB, you are doing a commutator to cycle 3 pieces and you do not leave the M slice off by 180 degrees like solving a single target does. Thus, you can put your setups for the second piece around the whole commutator, and they can be simplified because they don’t have to preserve the rest of the M slice.

For example, consider FL-LB. The basic M2 solution would be:-

(U’ L’ U) M2 (U’ L U) // solve FL
(L B L’ B’) M2 (B L B’ L’) // solve LB

Instead, you set up LB to the UB position:-

B’ // setup LB to UB
(U’ L’ U) M2 (U’ L U) // solve FL
M2 B // solve UB and undo setup

The same technique can be used to solve UB first of course. Take care that your setup doesn’t move your other sticker though! For example, LB-BR wouldn’t work.

Going back to the BU sticker, there’s a similar trick when BU is adjacent to LB, RB, UL or UR. When you set up one of those pieces to UB, you conveniently move the BU sticker to somewhere it can much more easily be set up from. For example, to solve LB-BU, just do a B’ setup, and then you can solve UB-BR and undo setup. This one’s definitely worth knowing.

*5. TuRBo-style shortcuts
*
For anyone not familiar with the TuRBo edges method, it works by using algs to solve pairs of pieces in the upper left and right positions, in each combination of orientations. You then set up each pair of pieces to those positions. A couple of similar tricks exist for M2 (although these differ from TuRBo because TuRBo uses a different buffer).

To solve UL-UR you can simply use U M’ U2 M U. That saves 13 moves over the basic M2 solution. With one-move setups, and the inverse U’ M’ U2 M U’, this can be used to solve any pair of “outer” stickers on the L and R layers (not both on the same layer of course).

For example, you can solve UR-FL with this: L’ U’ M’ U2 M U’ L.

Similarly, although a bit less efficient, “inner” stickers of the L and R layers can be solved with M U M U2 M’ U M’ and its inverse.

*Summary
*
One of the nice things about M2 is that it lends itself nicely to extensions like the ones above. You can create commutators on-the-fly for efficiently solving pairs of pieces, using simple patterns plus the basic M2 setups you already know. That's so much easier than learning a bunch of specific solutions for specific cases.

I hope this helps someone. If I missed any neat tricks, please post below!


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## h2f (Nov 27, 2015)

You've done the great thread!

Ad rem: 



> 1. Avoiding those nasty FU and BD algs



FU and BD with buffer DF has a great potential to be the comms. FU and BD are interchangeable when you do M slice move. So there's no need to shoot your buffer to UB in every case. It's enough to put your target to buffer and than interchange with BD or FU. For example BD-FL: you can do [D' L D, M'] and it's done. This is the same as your example: M2 (U’ L’ U) M’ (U’ L U) M’ but without setup move M2.


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## Berd (Nov 27, 2015)

Very nice job Mark.


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## muchacho (Nov 27, 2015)

Nice, I'm just learning M2 but I'll try to add some of the tricks as soon as I can, thanks!


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## youSurname (Nov 27, 2015)

Thanks a lot for this!

Shouldn't the FU/BD targets be

FU-s = M2 s M s’ M (where s/s’ are the setup/undo for the s sticker)
s-FU = *M’* s *M’* s’ M2
BD-s = M2 s M’ s’ M’
s-BD = *M* s *M* s’ M2


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## RicardoRix (Nov 27, 2015)

very cool.

struggled with the term 'if adjacent to a non M slice sticker', later you use 'This trick works for any of the non M slice pieces' the second term is better.
Also, 'If the M slice sticker comes first, the M2 comes first, and vice versa' does quite sound right, what about 'If the M slice sticker comes first, the M2 comes first, otherwise it comes at the end'


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## MarcelP (Nov 27, 2015)

This goes beyond my skill level  Nice Mark, I will keep this thread in mind for when I grow up.


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## newtonbase (Nov 27, 2015)

Thanks for this Mark. I'm working on this at the moment so it's a big help. 

h2f, that's very useful too. 
I have a couple of alternatives for these
UF-DB = M D2 M' D2
DB-UF = D2 M D2 M'


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## TDM (Nov 27, 2015)

Thank you! I was planning on doing some BLD this weekend, so I'll be practising some of these.


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## mark49152 (Nov 28, 2015)

Thanks all for the feedback .



h2f said:


> For example BD-FL: you can do [D' L D, M'] and it's done. This is the same as your example: M2 (U’ L’ U) M’ (U’ L U) M’ but without setup move M2.


You can, but then you have to learn or derive alternative setups for all the non M slice targets, rather than just reuse the basic M2 setups you are used to. That's OK but it's a step beyond Advanced M2, into the world of real comms .



youSurname said:


> Shouldn't the FU/BD targets be
> s-FU = *M’* s *M’* s’ M2
> s-BD = *M* s *M* s’ M2


Yes you are correct, thanks. Actually in converting from letters to sticker notation my tip for remembering these got broken as well so I've rewritten that bit.



RicardoRix said:


> struggled with [Mark's sloppy English ]


Thanks, all fixed


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## h2f (Nov 28, 2015)

mark49152 said:


> You can, but then you have to learn or derive alternative setups for all the non M slice targets, rather than just reuse the basic M2 setups you are used to. That's OK but it's a step beyond Advanced M2, into the world of real comms .



That's what I was thinking about. You're right.


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## h2f (Dec 12, 2015)

The idea for 2. Consecutive M slice targets

My idea is simple and obvious - if you deal with UB-FU stickers you just do M2 (UB target) and the alg for DB (M2 D U R2 U' M' U R2 U' M D') or the alg for FU (D M' U R2 U' M U R2 U' D' M2) and next M2 (UB target). The M2s in both cases cancel, so you do FU-UB or UB-FU with 3-cycle. In the first case: D: [M’, U R2 U’] in the second D: [U R2 U’, M’]. Both are 10 movers. I think it may have potetnial to make few tricks, for example FU-RB. If you do straight you do it with 20 moves (11 + 9). With setup B it gives 12 moves. With setup U' it gives 16 moves and a regrip. So it may be worth of drilling. On the other hand FU-RB you can make with one of the easiest comms [M', U' R' U]. So maybe it's only worth mention that there's a cancelation when you deal FU-UB. I've noticed it yesterday and I'm thinking about it. I'm not sure if it's good or bad idea.

Edit: I've corrected silly mistake.


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## Ollie (Dec 12, 2015)

Great tips, Mark! I used a lot of these when I was transitioning into comms, made it very easy.

One tip I'd like to add for the FU and BD targets is to think of them as being 'like' the UB target. In other words, solving them using the *'M method'*. It works in a similar way to M2 (although not exactly the same) but it was a good way for me to solve my FU and BD targets:



Spoiler: U' R' U (M') U' R U (M)



Instead of setting up to UB, you can set up to FU instead for some cases. 

1. Doing U' R' U sets up that more annoying RB target into your M layer in a different way.
2. M' solves it (compared to the usual M2 move)
3. Undo the set up
4. Solve your FU target by just doing M.





Spoiler: (M') U' R2 U (M) U' R2 U



Works in the same way.

1. Solve FU with an M'
2. Set up RD into FU 
3. M
4. Undo set ups.

It's just a case of remembering that it's always M' first, followed by M.



It's even useful for other cases:



Spoiler: DF-LB-RB



1. U L U' (M') U L' U' // first target
2. U' R' U (M) U' R U // second target. 14 moves instead of 18 with no rotations or double turns.



And some BD target example, although it's a bit more difficult to visualise and execute than the FU stuff:



Spoiler: DF-BD-RU



x' // now we can insert targets BD by treating it like our normal UB target (see where it's positioned after the x' rotation)

1. B' R2 B (M) B' R2 B // solve first target
2. (M') // solve second. The rule this time is now M is followed by M'





Spoiler: DF-UR-BD



x'
1. U R U' (M) U R' U' // solve the first piece
2. (M') // solve the second



Hopefully these make sense.


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## h2f (Dec 12, 2015)

Ollie, this is great! The U' R' U (M') U' R U (M) stuff I've started doing in every case I can - for example for LU target by setting U - but I wans't sure if it's good direction to follow. And tricks for DF-LB-RB was the second idea, but I havent drilled it yet.


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## MatejMuzatko (Dec 12, 2015)

Nicely written  I did something similiar in past, you can check it out in my signature if you want to


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## mark49152 (Dec 13, 2015)

Ollie said:


> One tip I'd like to add for the FU and BD targets is to think of them as being 'like' the UB target. In other words, solving them using the *'M method'*. It works in a similar way to M2 (although not exactly the same) but it was a good way for me to solve my FU and BD targets:


This is cool. When I started M2, I hated the FU and BD stickers, but when extending M2 with comms they are the most interesting because they are interchangeable with the buffer. It's worth noting that Ollie's, Grzegorz's and my solutions for DF-RB-FU are all commutators using the M slice to interchange:-


Ollie: U' R' U (M') U' R U (M) = comm interchanging DF-FU, with FU as the action spot
Grzegorz: (M) F' R2 F (M') F' R2 F = comm interchanging DF-FU, with DF as action spot
Mark: (M') R' B' R B (M') B' R' B R (M2) = M2 ((M) R' B' R B (M') B' R' B R) M2 = M2 setup to comm interchanging BD-UB, with UB as action spot

Grzegorz didn't post that but he advocated setups to DF so I took the liberty of attributing it to him . My solution (which I got from cubefreak.net) has the disadvantage of being longer due to the extra M2 and, for RB at least, longer setups, but has the advantage of using the usual familiar M2 setups to UB. I never thought of setting up to FU, that is a cool idea. I will have a play around with setups to FU and DF and see if I can get them to work for me without too much thinking .



Ollie said:


> DF-RU-BD
> 
> x' // now we can insert targets BD by treating it like our normal UB target (see where it's positioned after the x' rotation)
> 1. B' R2 B (M) B' R2 B // solve first target
> 2. (M') // solve second. The rule this time is now M is followed by M'


This one's interesting as well because the x rotation kind of acts like an M slice setup. Imagine you set up with M rather than x', meaning you'd use the usual UB setup of B' R B because you're not displacing the R/L layers. It would look like M (B' R B (M) B' R' B (M')) M' which is exactly my solution (M) B' R B (M) B' R' B (M2).

That's really nice if the rotation makes for a simpler setup. Going back to DF-RB-FU for comparison to the above solutions, (M') R' B' R B (M') B' R' B R (M2) could be done instead as x B' R' B (M') B' R B (M) x'.



h2f said:


> My idea is simple and obvious - if you deal with UB-FU stickers you just do M2 (UB target) and the alg for DB (M2 D U R2 U' M' U R2 U' M D') or the alg for FU (D M' U R2 U' M U R2 U' D' M2) and next M2 (UB target). The M2s in both cases cancel, so you do FU-UB or UB-FU with 3-cycle. In the first case: D: [M’, U R2 U’] in the second D: [U R2 U’, M’]. Both are 10 movers. I think it may have potetnial to make few tricks, for example FU-RB. If you do straight you do it with 20 moves (11 + 9). With setup B it gives 12 moves. With setup U' it gives 16 moves and a regrip. So it may be worth of drilling. On the other hand FU-RB you can make with one of the easiest comms [M', U' R' U]. So maybe it's only worth mention that there's a cancelation when you deal FU-UB. I've noticed it yesterday and I'm thinking about it. I'm not sure if it's good or bad idea.


I noticed the same thing and am also not sure whether it's beneficial because the alg is quite long. Trying DF-RB-FU again, it would be B (D M' U R2 U' M U R2 U' D) B' = 12 moves, quite a lot compared to the earlier solutions. I think the problem is that you already have two pieces DF & FU in the M slice ready for interchange, but this solution sets up by moving DF out of the M slice and RB into the M slice, which seems wasteful. (Look at the way the DF-FU-UB alg works - all three pieces are in the M slice initially, so one of them has to be moved out to allow a comm, and that's what the D moves do.)

I did try using this alg to solve cases like DF-RU-UL with a U' setup, when I was thinking about the TuRBo-style shortcuts, but I'm not sure that's a good idea either, because when you count the initial setup(s) to get the pieces into the U layer it all gets a bit long-winded. TuRBo-style tricks like U M' U2 M U are really only good because they're short.


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## h2f (Dec 13, 2015)

mark49152 said:


> This is cool. When I started M2, I hated the FU and BD stickers, but when extending M2 with comms they are the most interesting because they are interchangeable with the buffer. It's worth noting that Ollie's, Grzegorz's and my solutions for DF-RB-FU are all commutators using the M slice to interchange:-
> 
> 
> Ollie: U' R' U (M') U' R U (M) = comm interchanging DF-FU, with FU as the action spot
> ...



I think good way to organize it is to think about FU your BU target (Ollie's suggestion). But it changes the way of dealing with outer and inner pieces. For outer pieces setup move to bring them to FU is F/F' move and for inner pices is U/U' move. For UB it was U/U' for outer pieces and B/B' for inner pieces. To avoid F/F' moves you can do D/D' a setup to bring outer pieces to buffer. In this case buffer becomes interchange piece and you can think about FU as a your buffer in this case. But this may cause confusion. 



> I noticed the same thing and am also not sure whether it's beneficial because the alg is quite long. Trying DF-RB-FU again, it would be B (D M' U R2 U' M U R2 U' D) B' = 12 moves, quite a lot compared to the earlier solutions. I think the problem is that you already have two pieces DF & FU in the M slice ready for interchange, but this solution sets up by moving DF out of the M slice and RB into the M slice, which seems wasteful. (Look at the way the DF-FU-UB alg works - all three pieces are in the M slice initially, so one of them has to be moved out to allow a comm, and that's what the D moves do.)



I think you are right. We've noticed nothing but cancelation. 



> I did try using this alg to solve cases like DF-RU-UL with a U' setup, when I was thinking about the TuRBo-style shortcuts, but I'm not sure that's a good idea either, because when you count the initial setup(s) to get the pieces into the U layer it all gets a bit long-winded. TuRBo-style tricks like U M' U2 M U are really only good because they're short.



I think TuRBo algs may be fine for cases with pieces on F layer. For example M U M' U2 M U M' and it's inverse are fine to deal with outer pieces and U perm with M slices (7 movers) for inner pieces. I havent drill it yet but that is an idea I think about for a week.


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## achyut1 (Apr 18, 2018)

mark49152 said:


> Here are my five favourite Advanced M2 tricks. I found these scattered among many sources, so I thought it useful to collect into one place. I hope they help.
> 
> *What is Advanced M2?
> *
> ...


Thank you so much man...


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