Five cases with all four edges flipped. The four cases with none flipped are in 2-look PLL.
Goal
The first two layers and the four top corners are done. All four edges are flipped; the top shows only the center and the four yellow corners. One algorithm solves the cube.
How to recognize it
Words used here:
- : a top edge whose yellow sticker faces a side. Its color is the sticker facing up.
- : the edge has the color of the center of the side it sits on. A flipped edge can still be home.
- : the center on the far side of the cube (front and back, left and right).
Count the flipped edges and see where they are. Then find the edges that are home. If only one edge stays put, see which center's color the back or right edge has.
How to hold the cube
White on the bottom, with the top corners lined up with the centers. Every case is seen from this grip; the recognition text names positions as the cube starts.
The main idea
Opposite swap uses the OLL 20 algorithm from , plus a U' at the end.
The four cases with no flipped edge are Ua, Ub, H and Z in . This lesson and that one complete all 29 ELL cases.
Final check
The whole cube is solved. Turn U once more if the top is still offset.
Next lesson
Advanced last layer is done. To solve one-handed, look for the algorithms in the CFOP 2-look OLL and PLL lessons.