Leyaloids and Cross-Leys

The Leyaloids are the original beings created to synchronize with the Harmonic Servers and use song magic. They are artificial beings who are "coded" to have representations of their minds stored on the servers, which is part of the process that allows them to remotely synchronize with the machinery for song magic.
Originally, Leyaloids were hailed as a triumph of Mixolys's science. The ability to use song magic without a Pactone was no small feat. However, as the first Leyaloids matured and were put through more tests, flaws in their design because evident. Since their minds were so heavily dependent on the servers, Pactones were unable to synchronize with them consistently, if at all, due to the lack of organic "waves" that Pact Magic pulls from. Furthermore, they were extremely vulnerable to any damage to the servers, be it to the hardware or the software. A virus introduced to one Harmonic Server nearly killed every single Leyaloid attuned to it via data damage. The scientist teams working on the Leyaloids feared that the Leyaloids were too easily compromised, and put the project on hiatus, letting the current surviving Leyaloids disperse and do as they would like.
Time passed, and the descendants of pure Leyaloids caused a peculiar phenomenon. Leyaloid descendants, if they came in close proximity to a song server, would automatically be registered on the server, as though they were full Leyaloids. Some experimenting ensued, and these new Cross-Leys showed surprising improvements over their pureblooded ancestors. Due to having organic minds along with the copy that registered on the server, they could synchronize with Pactones and perform server magic, which granted them a great deal of versatility.
The majority of song magic users in Mixolys now are Cross-Leys. The original Leyaloids seem to have faded into the past, though some must still exist, or there would be much fewer Cross-Leys than there are.