Sonya Chaos is the XX-Class Apoptosis version of Sonya, who has absorbed both holy and dark energy.
Biography
(the following is based on untranslated portions)
On the Alice route, Sonya Mazda absorbs dark energy from Morrigan to become Sonya Chaos. Sonya Chaos summons Adramelech into the world, whom the Lilith Sisters and three Seraphs team up against. Luka's party fights and defeats her, but Adramelech persists (thanks to her ability to self-resurrect) and the world is gradually swallowed up by Chaos. Nuruko then reveals her true form as the Spirit of Chaos and reverts Sonya Chaos back to the (outwardly) human Sonya.
On the Ilias route, Sonya Mainyu absorbs holy energy from Gnosis to become Sonya Chaos. As in the Alice route, she summons Adramelech and is defeated by Luka's party. However, after being defeated, Sonya Chaos regains her personality as Sonya. She attacks and manages to defeat Adramelech, but receives a mortal wound in return. Sonya Chaos reverses the damage to the world and creates a copy of a Sonya from another world so that Luka won't miss her. She then dies.


