Deus activated biological computer Kadomony, generating the first mother being in response to Abel's contact with the Wave Existence shortly before planetfall. This original being emerges from the wreckage and gives birth to Miang, Elly, Cain and the Gazel Ministry, then returns to Kadomony's stasis pod where the being slowly rots over the next several thousand years. Miang begins her mission to supplement Deus' plans.

Miang awakens in a pair of identical twin sisters, using their connection to her advantage to conduct espionage within the Zeboim government. Upon finding out that a nano-engineer named Kim is working on a way to repair the genetic breakdown causing infertility in the vast majority of Zeboim citizens, she commissions Kim Kaseem to continue his work. However, when he moves to secure his creation for himself, she sends an assault team to requisition it and kill anyone in their way. Miang influences events to accelerate the death of the civilization so that humanity can 'reset' to a form more desirable for Deus, resulting in nuclear annihilation of the entire Zeboim civilization, which then sinks to the bottom of the Aquvy sea.

Unable to locate the current incarnation of the -Contact-, Miang cooperates with Krelian to clone an artificial -Contact- using Emperor Cain's DNA. The clone, which would later become Kahran Ramsus, gains awareness before even being born and develops an inferiority complex soon thereafter.

Miang dies of old age, and awakens in Karen Wong, Fei Fong Wong's mother, and uses her new position to conduct battery after battery of torturous experiments on Fei while his father is away, resulting in the inadvertent creation of Id. Miang stands by passively while Grahf attacks Khan Wong, triggering a spontaneous release of Fei's power. Karen regains control momentarily, long enough to throw herself in front of her son to save his life, and is mortally wounded in the process. Fei recedes into the “Coward” personality, shielding himself by displacing the tragedy and horror of these events onto his alter-ego, Id, who remains the dominant personality for the rest of his teenage years under Grahf's destructive tutelage.

Miang reawakens in a new host body, apparently in her early twenties, and begins to court Kahran Ramsus in order to gain power within the Gebler faction on Solaris. She begins to separate Ramsus from his close-knit friends in the Elements group to have tighter control over him. As Ramsus rises to power, Miang stations herself quietly behind him.

Miang is cut down by Ramsus in front of the newly activated Deus. The party witnesses her reawakening in Elly, who explains humanity's purpose relative to Deus shortly before being absorbed into its core. Deus utilizes its newly acquired Anima Relics and Krelian's nanotechnology to ascend to a higher, more advanced form than its original design was capable of, and climbs into orbit in an attempt to resume its journey. Fei gives pursuit in Xenogears, the only Gear left operational after the destruction of the Zohar Modifier, and battles with Miang in her final incarnation, that of the Urobolus. After Fei had successfully defeated her in this form, she had then ceased to exist. Once Miang is eradicated for good, Krelian is convinced of Fei's point of view and resigns from his original mission, opting instead to walk the Path of Sephirot and travel to the higher dimension from which the Wave Existence originated, leaving Fei and Elly to return to the planet in the Xenogears. The chains of fate are broken, and Fei and Elly become the final incarnations of their eternally returning personas, with the memories and experiences of all their past selves incorporated into them.