Centres and edges are fully reduced. The first two virtual layers are solved.
Hold the cube with yellow up. Put an edge group whose yellow stickers face sideways at top-front (UF).
1. Recognise the parity case
Count the edge groups with yellow facing up, ignoring the corners. Once the first two virtual layers are solved, a count of one or three indicates OLL parity. OLL here refers to last-layer orientation.
Every group must already contain two matching wings. If a group has two unmatched wings, return to edge pairing. A flipped reduced edge still has matching wings. If zero, two or four groups have yellow facing up, use the ordinary 3×3 cross cases.
2. Place the target at top-front
If three groups have yellow facing up, place the fourth at UF. If only one group has yellow facing up, choose any of the other three and put it at UF. Flipping it will produce an ordinary two-edge case.
Use a sideways whole-cube rotation or U before the sequence as needed. Keep yellow up at the start.
3. Follow the full repair sequence
Rw U2 x Rw U2 Rw U2 Rw' U2 Lw U2 Rw' U2 Rw U2 Rw' U2 Rw'
Read the sequence in sections, keeping the letters in the same order.
Rw U2 xRw U2 Rw U2 Rw' U2Lw U2 Rw' U2Rw U2 Rw' U2 Rw'
Rw and Lw each turn two layers. For x, rotate the whole cube in the direction of R, then use the new face directions. Wait until the repair is complete before checking the centres.
4. Return to the solve
Once you’ve completed the sequence, reorient the cube with yellow up. Check that the centres and edge pairs are restored. Count the edge groups with yellow facing up again. If the cross is still incomplete, return to the yellow-cross lesson.
This repair fixes the orientation exception. Other last-layer pieces may still need solving, and you may still encounter PLL parity later.
Need a reminder of the move notation?
R right · L left · U top · D bottom · F front · B back. A letter on its own means a 90° clockwise turn as you look directly at that face. An apostrophe (′) reverses the direction. A 2 means a 180° turn. Keep the same face at the front throughout the algorithm.
Rw turns the rightmost two layers together. 2R turns only the second layer from the right. 3Rw turns three layers. x rotates the whole cube like R, so the old front becomes the new top.
Watch, then try
Work through an example
Start by stepping through one move at a time. This prepared example shows a specific action. Use the lesson’s setup instructions to recognise when to use it on your own scramble.
Watch one worked example
The prepared cube has its flipped pair at UF. Notice the whole-cube x rotation, two-layer wide turns, and the restored edge pair at the end.
Example grip: Start with yellow on top, blue at the front and red on the right. Follow any written instructions for rotating the whole cube.
0 / 18
Loading 3D cube…
Prepared position · 0 / 18 moves
Use Next move to follow the sequence.
Drag to inspect other faces. Use the arrow keys to rotate the view when the cube has keyboard focus.
Copy this exact example on your own cube
Start with a solved 4×4, with yellow up and blue at the front. Apply the setup below from left to right to create the example’s starting position. Keep this example separate from the scramble you’re solving throughout the course.
Rw U2 Rw U2 Rw' U2 Rw U2 Lw' U2 Rw U2 Rw' U2 Rw' x' U2 Rw'Then follow the lesson sequence. If your cube has a different colour scheme, use the relationships between your own colours to identify the equivalent pieces.
Compare the starting position and the result
Drag each cube to inspect its other faces.
Explain it to yourself
Check your understanding
Now use your own cube
Your turn
If you encounter this case during a solve, pause at the yellow-cross step. Put the target at UF and follow every move. Then turn the cube so yellow is up again and identify the new cross case.
Open a 4×4 Digital Cube for practiceOpens in a new tab so you can keep this lesson open while you practise. Check for yourself whether you’ve met the lesson goal. The Digital Cube doesn’t assess your result.
If you get stuck
The front face changed during the animation.
For x, rotate the whole cube and use the new face directions for the remaining moves.
The cube is not fully solved after parity.
Recheck the yellow cross and continue solving the last layer as usual. This repair fixes only the flipped edge group.
Before moving on
Check your result
Your cube at this stage
The flipped-edge case is fixed
The edge groups are paired and the yellow edges now show a standard orientation case. This example has a yellow cross, with the corners still to solve.
Confirm these on your cube. Watching the animation alone does not complete the lesson.
Tick each item once you can do it yourself.