Advanced F2L Techniques

So, hi guys. I received a ton of requests for an advanced F2L video. Many people are struggling with F2L and want tips on how to get faster. You have to keep in mind that there is no huge secret that I can tell you that would make you suddenly drop 10 seconds in averages of F2L. Rather, it's more about knowing many, many small disconnected shortcuts and using them all effectively throughout your solve. So in this video I'll go over some of those that I could think of, and I'll just be throwing random tips and tricks at you and hoping that most of it sticks. Finally, as a disclaimer, I have to warn you that this video is for advanced cubers only. I'm thinking at least 45 seconds averages and also a pretty good familiarity with F2L. Now that we have that off the table, we can get started. Okay, so the single most important thing while solving the F2L is that you have to be constantly looking ahead. You have to be comfortable with all the algorithms that you use for F2L, even when you do it intuitively. And you have to be able to execute them all from just muscle memory so that your conscious mind can work on tracking pieces along the cube and just concentrating on what's gonna come next. So for example, I know that these two in this case have to come here, but I also see that in the top layer I have this corner and this edge which form a pair. So as I solve this, these, this pair, I'm tracking that pair around the cube and I'm seeing where it goes, and I know which case is gonna come next because I tracked them. And as I do that one, I can tilt the cube and look— try to look ahead always, and I know that the edge for this corner must be this one because it's not here and it's not anywhere in the top layer, so I can just perform that one. And using that same principle, I can just execute the entire F2L. You just have to be always looking ahead. The next very, very important thing is that you must reduce the number of cube rotations you do. Doing cube rotations such as Y or Y' is okay as long as you try to minimize them. You'll have to do 2 or 3 at most in each solve, but doing Y2 rotations like so is just terrible, and you should never have to resort to doing that. So for example, after I insert this pair, I have this edge here, this corner here. So these two need to come here. After I insert this pair, I'm tracking those two, and I know that the edge is now here, the corner here, and instead of rotating my cube so that I can solve it, I'm gonna use my left hand to solve this case, just so that I don't have to do a cube rotation. So the use of left hand is very important, and you have to be very comfortable using your left hand just like using your right hand. Another very important thing is that you have to keep track of what slots are filled and what slots aren't filled. So for example, here I have none of the slots filled. For example, if I want to insert this one, uh, it's gonna help me greatly to know that this slot is not filled because then I can just hide like so. Otherwise I would have to actually rotate the cube, hide like so, and do it like that way. But since I know this is not filled, I can just and solve it very easily. So it's very important to know which slots are filled, and as you rotate the cube, you have to update your mental image and always be aware of which slots are filled and which aren't. And in that way, you can hide pieces more efficiently and you can reduce the number of moves and cube rotations that you make in your solve. Okay, so those are some general techniques. Now I'll go into a little more special cases that come up Sometimes when you solve the F2L, you get pairs that form by accident on top. It happens oftentimes. So for example, if I were to just insert this pair, I see that I would break up the other pair here. That means that that forces me to insert this pair first and then the other pair. So you have to adjust your solve sometimes when these cases come up. A little more non-trivial example of that is when you have pairs like this formed, and if you are to insert this pair just like so, you are separating this pair here. So you have to be able to insert this pair another way, and it turns out there is another way, and it's R' F R F'. So sometimes there are a little more clever ways to insert that do not break up pairs. So, uh, you want to try to preserve your pairs. Okay, you have to keep in mind that F2L is a very, very versatile method, and nothing that I tell you comes without exceptions. So I just told you seconds ago that if you wanted to solve this one, put it here, but have this one filled, you do not want to hide the corner like so and popping this pair out, because you will mess it up. However, doing cube rotation and solving it this way is very costly as well, because cube rotations are very, very bad. So actually what I do in practice is that I ignore the fact that this pair is already filled and I just stubbornly solve this one anyway, and as I put it back, I overshoot and put this pair back to where it belongs. So sometimes you have to be prepared to make some sacrifices just to save up, you know, cube rotations or moves or whatever. Okay, I want to touch on empty slots again. Imagine you had this situation, but all the F2L pairs were filled in. This would be a disaster to solve in a normal way. However, if you know that you have one adjacent empty slot here, then you can use that extra degree of freedom to solve this much faster. So for example, in this case, a better solution would be F' L' U2 L F R U R'. So without having that slot empty, you would not be able to do this because you would screw it up. So the use of empty slots is important and it can sometimes save you a lot of moves. I'll give you a link to a website that goes over some of these things, such as empty slots and some of the stuff that I'll go over in a second. Okay, next. In practice, what happens a lot is that your edges and your corners are actually stuck in the bottom layers instead of being on top in the working area. So you have to know quick ways of taking them out and forming pairs that are inserted faster. So for example, this case would be a disaster to handle intuitively, but there are ways to do it faster. For example, in this case, I can do something like L F2 L' F' F U' F, like so. So that greatly reduces the number of moves that you have to make. Okay, I'm now going to quickly talk about multislotting. Many of you probably know about multislotting. It's a way of solving an edge-corner pair while preparing another pair for insertion. So for example, this corner, this edge have to come here, this corner, this edge should come here. I could just trivially solve this one and then do this one later, but the multislotting solution would have me do L' first R' U R' U' L' and now you can see that they're set up for a very quick insertion as well. So multislotting is all about small tricks like this, but I find that it only works for very, very special cases, and in most cases it's not too useful. And I actually think that recognizing those cases might take more time than actually solving the two cases separately. So I don't use multislotting right now, but Maybe I'm just stupid, maybe I'll realize later on that I'm not making any sense right now and I'll make a video on multislotting, but from what I've seen so far, I'm not too impressed with it. Lastly, I want to introduce you to a technique called misaligned pairs. So this is a misaligned pair. Now, when we talk about filling in slots, we always think of the edge and the corner pairs together. Like this is a slot here, but you have to realize is that this slot is actually made of the corner and the edge piece, which are separate on the Rubik's Cube. So what you can actually do— this corner has to come here and this edge has to come here— is that you can pull a trick and actually solve both of these at the same time. Let me show you what I mean. Let me do this move, and now as I insert this pair here, I solved the edge for this slot and the corner for this slot, and now I'll just move it back. So using this way, you can solve different slots with one insertion. I mean, it's a very neat idea. I think it's really cool, but I don't use it in my solves right now, but I think it's got potential, and I'm definitely gonna look into this in the future. Okay, so I realized this video had a lot of content and new ideas. That's just because F2L is very versatile and there are many shortcuts that you can take when you solve it. I have to wrap up the video because I'm nearing 10 minutes, but I could go on for hours. But lastly, I want to say that there are many cool F2L solutions to special cases that use all kinds of cool tricks, and I'll provide you with two examples now, and I'll give you a link in the video description to where you can look up more. And that's going to be the end of the video. So, for example, this case. Edge here, corner here, move that to come here. Beautiful, very short. It was like 5 moves. This case here is a huge nuisance. These two don't align, so you can't just take them out, but they have to come here. It turns out that there's a very fast way to do it. Also like 5 moves. So anyway, I'm posting all this in the description. See ya!