Start Learning

If you’re here, you probably want to learn OBL! This page will tell you how to use the site.

References

If you’re already familiar with the basics and are just looking for references, use the below links.

• Weighted OBL Tree: All unique OBL cases organized by slice count; cases are weighted by how often they’re likely to appear in an OBL solution, with more likely cases in the middle.
• Faces List: Learn the names and mnemonics for every face.
• Cases List: Best algs, alternate algs, and related cases for every OBL case, including mirrors.
• Other Resources: A collection of other helpful resources, for OBL or for Square-1 as a whole.

Overview

In the same sense that we can say there are 4 “levels” of difficulty to cubeshape (beginner methods that either group all edges or group 6 corners; intermediate methods like kite/scallop; advanced full CS; and expert CSP), there are essentially four levels of OBL. These are as follows:

• Beginner: regular old CO into EO
• Intermediate: all short OBLs and their pseudomirrors, mostly blockbuilding on any remaining cases
• Advanced: all 74 standard cases memorized
• Expert: all mirrors (L/R, U/D, color-swapped) memorized, intentionally choosing non-slice-optimal for some cases because of better recognition/ergonomics/etc.

Beginner -> Intermediate

In this guide, we’ll assume that you already know CO into EO. So, congrats! You already know the following 11 cases:

• CO covers 4 cases: Kite / Kite (the only 1-slicer); Tent / Tent; Kite / Pinwheel; Pinwheel / Pinwheel.
• EO covers 6 cases: 1E / 1E; Eopp / Eopp, aka M2; Eopp / Eadj; Eadj / Eadj; 3E / 3E; 4E / 4E.
• And then there’s 1 0-slicer (the solved state).

Don’t worry if you don’t know what these mean yet, just know that you’re already 14% of the way to “advanced”. Good job, you! Your next step will be learning all of the 2- and 3-slice optimal cases.

There are only 5 2-slicers, and you actually already know three of them: Tent / Tent, M2, and Pinwheel / Pinwheel. So really you only have to learn two new cases:

• m2 (the corner version of M2); and
• Dish / Dish.

Click on the links to those cases to get started on learning them! As you do, try clicking into some of the links on each case page. In particular, click into the cases’ face page(s) to see more information on them, e.g. why we’ve named those faces the way we have.

After this, you’ll want to start on the 3-slicers. We’re planning on writing a more in-depth guide, but for now just go to the Cases page and click to sort by optimal movecount. There will be some mirrors; you don’t need to worry about those yet, just pick one and learn it.

As you’re working on the 3-slicers, more thoroughly learning all the different faces will help out a lot. You can do so by clicking the “Up” button on any individual face’s page; through the navbar’s dropdown, under “Learn”; or by going directly to the Faces page. They’re sortable by “E/C Type”, which is just a count of edges and corners of a single color that have been swapped with the opposite face. Only another face of the same E/C Type can be opposite it, so try sorting by that column as well. Some of the individual faces pages also have recognition tips, especially the left/right ones, so check them out!

Intermediate -> Advanced

TBD; check back later!

Advanced -> Expert

TBD; check back later!