3x3 CMLL Pi X algorithm

Solve the four upper corners in Roux after building both side blocks; the remaining edges are solved later.

Pi X belongs to the Pi group in CMLL.

Recognize this starting position

In the inverse-derived training position, the upper-face color points upward at these corner positions: none. Upper edges with that color facing up: UF, UB, UR. Reading each side’s upper corner stickers left to right when facing that side gives F: R U; R: L L; B: U R; L: U U. The letters identify colors by their reference faces.

Execute the algorithm

R' F2 D R2 U' R2 D' F2 R

The opening is R' F2 D; the final segment is D' F2 R. This version contains 9 face, wide, or slice turns and no whole-puzzle rotations.