The thirteen mortals were split into two categories after they were informed of their purpose in the realm of Constellations.
The first group involved those who would undergo trials to get the attention of a Constellation. Those under this banner were Serah, Aloe, Ciara, Ana, Aurora, Lemi, Jerry, Z'ark, Beruel, and Gerard.
The second category belonged to those who would be training under their respective Constellations. In essence, Kuzon, Edward, and Maria.
Despite being divided into two main groups, each individual had their own compartment where they would undergo their trial.
It was a personal journey for everyone, thus they were separated into what could only be defined as distinct realities all locked within the Constellation Realm.
With each person in a world of their own, they would undergo trials unique to them. As for the Constellations, they would observe the prospective Hosts, as well as the ones who aimed for improvement.