The dimensional transfer is how characters from Forgotton Ubiquity or other worlds can transport to the world of Kriosis. There are three ways of which this occurs:
Beings that die and sacrifice themselves for a noble cause are often reborn into the new world of Kriosis, retaining their most important memories only. They may also retain a similar appearance, or have it be changed entirely.
Different dimensional portals are scattered between the worlds, which all lead towards the world of Kriosis. Done once by Echo.
The special ability known as "Galactic Pulsar" is capable of performing dimensional travel. Done once so far by Ryker Hikaru, teleporting him, Asuna, and Taiven