z2 // inspection
R2 U' U' R' U' R2 // cross
z y U' U' R U R' // 1st pair
y' R U' R' U' y' R U' R' // 2nd pair
U R U' U' R2 U' R2 U' R' // 3rd pair
y' U' R U' R' U2 R U' R' // 4th pair
U R U R' U' R' F R2 U R' U' z x U' // OLL
z' R U' R U R U R U' R' U' R2 U' U' // PLL