Crux is a completely barren world. It is one of the smallest of the Spheres, less than half a kilometer across. It is located almost directly above the center but is far enough away to be difficult to see from any nearby spheres. There are no races native to Crux as it is totally barren and unable to support life.
It's entire surface is perfectly flat except for narrow canals filled with liquid mana and a spiral staircase leading downwards from its pole. Below the surface lie countless hallways lit by the cold green of mana lamps fueled by the liquid mana that inevitably makes its way below ground. The system of hallways is extensive, following a pattern of concentric circles underneath the entire surface and extending several layers downwards. The walls of the hallways themselves are covered in writing that details the history of the warrior Cross.