Parity: cross 2
Step 1 / 13
r': Right inner layer: turn 90°, front face goes down (Written as TR' in the textbook)
Back edge: the left wing belongs to the front edge, the right wing is flipped. Front edge: the left wing is flipped, the right wing belongs to the back edge.
The last two edges at the front and back of the top.
Step 1 of 13: r'. Right inner layer: turn 90°, front face goes down