CEOR is a Rubik's Cube method designed for use in one-handed speedsolving. It can be seen as the counterpart to LEOR because, aside from the early corner permutation aspect, the steps are the same. Since the early 2000's CEOR has been created multiple times by different proposers and under different names. Because of this, it was decided to group all of the proposals into a single method. The name CEOR was created to match LEOR and the C is short for Corner Permutation (CP).
1. CPFB: Permute all corners while solving a 1x2x3 on the left side. This step is commonly solved in two steps. First all corners are permuted while solving the 1x1x3 line at DL which consists of the DFL and DBL corners and the DL edge. Then U, u, R, and r moves are used to solve the FL and BL edges and the left layer center.
2. EOdM: Orient all remaining edges and solve the DF and DB edges.
3. RB: Solve the right side 1x2x3 - also referred to as right block or RB.
4. 2GLL: Complete the last layer using 2GLL which consists of 84 algorithms.
- Great ergonomics for one-handed solving. After the initial few pieces are solved, only R, r, U, and u moves are required.
- Planning corner permutation during inspection takes away time to plan further into the solve.
- Compared to a non-CP first block, additional moves are required to build CPFB.
In 2003 Gilles Roux submitted the idea for this method to the SpeedsolvingRubik'sCube Yahoo! Group. He also used the method in the Fewest Moves Challenge (online contest). In Gilles Roux's example solve, the initial 1x2x3 was solved on the D layer and U, u, and R moves were used to orient all remaining edges and place the FL + BL edges and the left layer center. The method wasn't developed any further because he didn't believe that it was competitive in speedsolving.
In 2013 Noah Arthurs proposed the method under the name Noah's CP Block 2.0. The initial steps for CPFB were to solve a 1x2x3 on the left, place the DFR and DBR corners without regard to their orientation, then solve the corner permutation of the U layer corners. Later Noah updated the method to follow the steps of CPLine then add the FL + BL edges and the left layer center. Noah's CP Block 2.0 was the first proposed and fully developed method to follow the steps of CEOR.
In 2015 Joseph Briggs proposed this method, and a corner permutation recognition system, giving it the name Briggs. Joseph Briggs also applied the early CP concept to another method called B2 (Briggs2) Method.
In 2020 Yash Mehta proposed a method called YruRU which follows the steps of CEOR. Along with the proposal was a new corner permutation recognition system as well as a couple of techniques to be applied during the edge orientation and blockbuilding steps. When this method was first presented, it received a lot of criticism for having the same steps as the Briggs method.
There are additional methods that have been proposed which follow the same steps or are very closely related to CEOR. Two examples are C2GR by Zbigniew Zborowski and 2GR. Another related method which doesn't completely follow the same steps as CEOR but does eventually get to the EOCP 2x2x3 state is TruSRU.
In 2021 in a CP method history post by James Straughan it was proposed that each of the methods that follow the same steps be consolidated into a single method. Joseph Tudor (PapaSmurf) suggested the name CEOR and both Joseph Briggs and Yash Mehta agreed to this new classification.