So from now on just continue and solve the cube like it was a 3x3 Rubik's cube until the last layer (just before orienting the last layer). The reason to solve only till the last layer, and not complete the cube, is because there are 2 special cases in the 4x4 cube that can occur, which are impossible in the 3x3 cube.t is best to master the 3x3 solution before going for the 4x4, though it's not a must. Same move notation rules apply for the 4x4 cube as well, with only 2 differences: 1. Lower-case letters mean turning 2 layers of the corresponding face.