What separates a Lucid from mundane humans is their bond to one of the Four Outer Realms. The nature of these Realms is a highly debated topic of cosmologists and philosophers. What most agree on is that these are places of power. While some call them magic others places more scientific terms on them. They are the supernatural. Places beyond the comprehension of mortals that thrive outside the mundane world. Lucids are able to tap into the forces of their Realm, channel it shaping it to their needs.
The Player chooses one of the four Realms for their Character. This is the Realm the Character first experienced and caused their Elucidation. They are bonded to their Realm on a metaphysical level. At the time of their Elucidation the Realm becomes as much a part of their Character as their genetics.