I’ve wanted to make this Two-Look OLL tutorial for a while, and finally found the time. Although the video embedded below is comprehensive (read: long) and should stand alone, this post’s further background and table of algorithms should help with learning/practice.
What is OLL?
The third-step in 3×3 solving under the CFOP/Fridrich Method is OLL (Orient Last Layer). By the OLL stage, with the Cross and F2L complete, the bottom face and first two layers will be solved. The goal of OLL is to orient the up face stickers (generally yellow for white-on-bottom solvers so that all are facing up and none are facing “out.”
There are 57 possible cases/states at the OLL stage, too many for most cubers to learn/remember all solutions. (Two years in, and I know only about 30 of them….) Two-Look OLL is designed to lighten the burden by breaking OLL into two steps. The first step (or “look”) of Two-Look OLL is to orient the four edges, forming a yellow cross or plus-sign (ignoring the edges). The second “look” orients the four corners so that yellow faces up, completing the top face. The center cubie is, of course, fixed and can never be “un-oriented.” As the Speedsolving Wiki summarizes:
[Y]ou do not need to know all 57 OLLs to use 2-look OLL, rather the system is divided up. By first orienting the edges (3 cases), then orienting the corners (7 cases), orientation of all pieces on the last layer is completed.
I think we all can agree that 10 cases is better than 57!?! Here’s a video teaching and contextualizing them:
Following up on my V Perm post, I thought I’d give another go at doing a multi-cam of a couple other long PLLs — the two Rs:
Over the past month or so, I’ve been trying to eliminate U2’ from most algorithms that call for a double-U turn. When I first began cubing, I realized the exact equivalence between a U2 and a U2’ in terms of the position of the cubies. What I didn’t realize was that U2’, in most cases, is more awkward than U2 and often leaves hand/finger positions incompatible with more efficient finger tricks. Also, now that I do double-U flicks with my right hand (while struggling to do double U’ flicks with my left), it’s just a lot slower to do U2’.
This video (and the chart below it) shows that I’ve replaced U2’ in most algorithms, but have purposely left it as U2’ in a couple others:
z D’ R2′ D (R2 U R’) D'(R U’) (R U R’) D (R U’) z’
It’s not weird to have a favorite algorithm, right? I mean, look at unboxing or review videos, and each cuber seems to have a go-to move. For a while now, mine’s been the V Perm — the PLL that (a) swaps opposite corners and (b) swaps the adjacent edges next to them. I hated the V Perm, as I first learned it: R’ U R’ d’ R’ F’ R2 U’ R’ U R’ F R F. That algorithm was clunky, without a good flow.
Enter jskyler91, who posted this “non-standard” V Perm execution, which flows smoothly with no re-grips:
z D’ R2′ D (R2 U R’) D’ (R U’) (R U R’) D (R U’) z’
Since it’s one of the more complicated executions in my repertoire, I thought it would lend itself to a multi-angle video. I did something similar, when I was still learning the algorithm, and I wanted to update it:
After painstakingly modding my Shengshou v4s a couple months ago (mod post coming soon), my interest in 4x4s has waxed and waned. On the one hand, I find it a welcome and more challenging distraction from 3x3s; on the other hand, those damn parity algorithms!?! I have finally committed them to muscle memory and am now trotting along at a 2:20 average using the Yau variation of the reduction method. (For more on Yau, and especially the cross-on-right variation that I find easier, check out Cyoubx’ really good Yau intro video.)
For months, parity was my albatross. I finally conquered it, so to speak, not only by finding and learning algorithms that worked for me, but also my learning about the root causes of parity. This was by far my deepest dive into puzzle theory and its associated patois. Keep reading past the jump for much more on the types of cube parity, what causes each, and, most importantly, what we really mean when we sloppily say that a cube has “parity.”
If you’re just here for the algorithms, look no further:
 Rw U2 x Rw U2 Rw U2 Rw’ U2 Lw U2
Rw’ U2 Rw U2 Rw’ U2 Rw’
 (Rw Lw) U2 Lw’ U2 Rw’ U2′ x’ U2 Rw’ U2′ Rw U2 Rw’ U2′ Rw2 U2
Uw2 Rw2 U2 r2 U2 Rw2 Uw2
Here’s a (now muted due to copyright claims) video showing each:
Generally, I find the OLL “dot” cases frustrating — there are a bunch of them, they’re hard to identify/distinguish quickly, and their algorithms are long. A few months ago, I worked on a couple OLL dot cases that I had previously two-looked. Those came rather easily. Then I got side-tracked by the Megaminx, 4×4 modding, and PLL time attacks.
I decided to work on more OLLs last week, after stumbling onto Ottozing’s very good Cubing World video showing all of the dot cases. Specifically, these three:
(r U R’ U) (R U2′) r2′
(U’ R U’ R’) U2 r
M U (R U R’ U’)
M’ (R’ F R F’)
(r U R’ U’) (L2 l2′) (U R U’ R’) U’ M’
I’ve been on a Megaminx kick for the past 10 days. After posting that 10-minute (plus) non-last-layer solve, I practiced a bit more and finally did learn the last layer (beginners’ tutorial coming soon). I’m down to about 6 minutes now for a full solve. With one exception that I’ll point to in my upcoming last layer post, I couldn’t find many good Megaminx tutorials online. Instead, I kept bumping into statements that solving a Megaminx is just like solving a 3×3 — but with a bunch more F2L steps. Yeah, that is basically right. But not entirely.
On a cube there are just 4 F2L slots. Except for some incremental efficiency gains, there’s really no magic to the order in which you fill those slots. On a Megaminx, order does matter — at least, I found that certain face/slot orders flows more smoothly, with a lot less potential for accidentally destroying already-solved portions.
I also found that there will always be one tricky V-shaped slot formed by an edge-corner-edge (ECE) trio. In the end, it turns out that’s it’s not that hard to form and insert the trio without breaking up the solved neighboring faces. I just wish someone would have created a clear tutorial one it, since it’s not entirely intuitive. Having figured out a technique that worked well for me, I decided to do a quick walk-thru video showing the face/slot order I use and then explaining the way I fill that ECE trio:
This is a beginner doing a beginner’s work; there’s some inefficiency and excess hunting throughout. Continue reading