A simple magic cube is the lowest of six basic classes of magic cube. These classes are based on extra features required.
The simple magic cube requires only the basic features a cube requires to be magic. Namely; all lines parallel to the faces, and all 4 triagonals sum correctly. i.e. all 1-agonals and all 3-agonals sum to
No planar diagonals (2-agonals) are required to sum correctly, so there are probably no magic squares in the cube.