3x3 CMLL Pi Down Slash algorithm

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

Pi Down Slash 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, UL. Reading each side’s upper corner stickers left to right when facing that side gives F: R U; R: B R; B: U F; L: U U. The letters identify colors by their reference faces.

Execute the algorithm

U F R' F' R U2 R U' R' U R U2 R'

The opening is U F R'; the final segment is R U2 R'. This version contains 13 face, wide, or slice turns and no whole-puzzle rotations.