During the creation of The World, Harald Hoerwick created the Morganna Mode Gone system to oversee the birth of the Ultimate AI from the personality data of the players of The World. Eventually, Morganna realized that after the birth of Aura (AI Ultimate), she would have no purpose. After the birth of Aura, Morganna continues her actions to assist in the development of AI Ultimate, but in a different approach, causing it to create the 8 phases of the Cursed Wave. The 8 phases had the objective of capturing/destroying Aura so that Morganna restarted its original purpose indefinitely. During Second Network Crisis events, Morganna creates the phases in the same order (Skeith, Innis, Magus, Fidchell, Gorre, Macha, Tarvos, Cobernik) as the Epitaph of Twilight poem. Each phase appeared in the battlefields of The World, putting in coma to all the players who were defeated by the same phases, even they affect areas outside the World, altering the electrical installations, or relative use of the net in Japan. Thanks to a group of players, hackers and administrators, Morganna is defeated and remains inactive in The World, prevent it from being harmed again. The 8 phases are sent to the sea of data, from where they can not return.
Avatars in the G.U. Games
During Project G.U., the 8 Phases' data, also known as Epitaphs or Morganna Factors, were recovered from sea of data and incorporated into special PCs called Epitaph-PCs, allowing the player controlling the PC, known as an Epitaph User (碑文使い), to summon the phase as an "Avatar". The eight main characters of G.U., also known as the Infinity Eight, are all Epitaph Users. Only rare people with compatible personalities, known as "Chosen Ones" (適格者), can become Epitaph Users. "Chosen Ones" have a connection emotionally to the Avatar they're compatible with. Ordinary people lose consciousness when attempting to use an Epitaph-PC. When "awakened", Epitaph Users can call forth their respective Phase and fight in Avatar Space, an extra dimension that exists outside of the perception of normal users, but parallel to and in direct interaction with the rest of The World R:2.
In addition to the Infinity Eight, known chosen ones include Shino Nanao, who was once the Epitaph User of Innis, and the eight Chosen Ones found by the R.A. Program. Some Avatars appear quite different from the original 8 Phases, incorporating some elements of the appearances of the players controlling them. In .hack//G.U.+, a character named Kazumi controls the Dummy Morganna Factor that Jyotaro Amagi created.
Though the Avatars in G.U. look vastly different to the originals (being more humanoid), many retain traits, such as Magus' long tail, Tarvos being impaled on a spike, and Macha's flower motif.
Avatars in the G.U. Novels
In the .hack//G.U. novels, the Avatars (巫器) are eight weapons with the skill Data Drain. Much like in the games, they are the manifestation of an Epitaph-PC's "Epitaph" and can only be seen by Epitaph Users. When two Avatars touch, an Avatar Space (巫器空間) is formed. Avatar Space is a white space where the thoughts and wills of the users blend. Haseo's weapon is similar to his Lost Weapon. Kuhn's lance and Endrance's rapier also make appearances, yet it is unknown how they may relate to their Lost Weapon's.
- In the Japanese version, Chosen Ones were referred to as "candidates", or "qualified". The reason for the change to a more auspicious name is unknown.
- Cobernik and Innis are the only phases having visibly AIDA (black bubbles).
- Magus and Fidchell are the only phases that were never infected by AIDA.
- Haseo was infected by AIDA, but managed to get rid of it before use Skeith.
- Innis is the only avatar that had more than one User that can use its power in addition to it was stolen from Epitaph User.
- Shino was in a coma, so Innis sought another candidate, finding Atoli, but during .hack//G.U., AIDA steals the Avatar and uses its power, then AIDA transfers Innis to Sirius, however when he is defeated, Innis returns to Atoli just to be manipulated by Sakaki (with the help of AIDA) and imprison all Moon Tree members in to their @Home.
- Skeith is the only one who has absorbed the other Phases, however, the Epitaphs can still be used by the Chosen ones.