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2GR (2-generator reduction)

2GR is an advanced speedsolving method that reduces the cube to the <R,U> subgroup, allowing for a very ergonomic F2L step and an 84-algorithm 1-look LL.

Projected movecount: 49
Moves planned in inspection: 11
Algorithm count: 84

The main difficulty in reducing to the <R,U> subgroup lies in recognizing and applying a "CP fix" that restricts the 6 corners movable by the R and U faces to 120 of 720 possible permutations available to them.

Unlike past attempts at performing this CP fix (like ZZ-Porky and CPLS), 2GR performs this reduction early enough in the solve that it can be planned in inspection. This avoids issues with recognition time and takes less moves to perform. To accomplish this, the entire cube group is reduced to the <R,U,F2,r2,u2,f2>, <R,U,r2,u2>, and <R,U> subgroups through the EOPair, CPLine, and Block steps described below.


Outline of Substeps

Scramble R' D' L' D F2 D' B' U F D2 B' L' U2 F' U2 F' U2 F L D2
1. EOPair: create a 2x1x1 corner-edge pair at DBL-DL while orienting all the edges x y' r' U R F' u' r' U' f2
2. CPLine: complete a 3x1x1 line on LD while reducing the remaining 6 corners to <R,U> r F' r'
3. Block: expand the line into a 3x2x2 block U' R E2 R' U' r2
4. F2L: complete the F2L R' U2 R U R' U2 R U' R U R U R
5. 2GLL: complete the last layer in 1 look R' U2 R U R' U R U R U R' U R U2 R' U2 // 46 moves