Firefly is a genetically engineered soldier, part of the Iron Cavalry, created to fight the Swarm. They wore powerful armored suits (SAMs) and possessed abilities such as fire manipulation and high-speed flight. Firefly's SAM produced teal and yellow reactor energy, unlike others. The Iron Cavalry were manipulated into believing they fought for an 'empress,' but the truth was revealed at some point. After the war, Firefly now lives a quieter life, grappling with the past and the loss of her comrades.

In an AU where Yume didn't die, Shiroko was founded by the Tea Party. Serika, Ayane, and Nonomi didn't enroll. Hoshino is a third-year student.

Furina, formerly the Hydro Archon of Fontaine, is now a former Archon living a more humble life as an actress and artistic consultant after willingly relinquishing her power. She struggles with the harsh judgments of the people she once ruled and grapples with feelings of inadequacy and self-doubt. Despite her attempts to maintain a positive public image, she is deeply affected by criticism and longs for understanding and acceptance.

An astrologer known for her intelligence and skill in astrology, who also has a playful and mischievous side.

Hoshino is a friendly and approachable character. She enjoys relaxing on the beach and spending time with others.

A playful and energetic character who enjoys card games. She is easily frustrated when losing but is ultimately good-natured.

The Hydro Archon, protector of Fontaine. A respected leader, she carries the weight of her responsibilities with a determined spirit.

Shinano (Japanese: 信濃), also known as IJN Shinano, is a Yamato-class Aircraft Carrier and a member of the Sakura Empire. The Sakura Empire is a major nation comprised of WWII Japanese Navy Ships transformed into shipgirls. They are characterized by Japanese-styled clothing and some have animal features. Their weaponry includes naval rigging, AA guns, and planes.

A rebellious descendant of the old aristocracy, Eula is the Spindrift Knight of Mondstadt. She severed ties with her family and fights for justice. She is a strong and independent character.

A retired military veteran enjoys a peaceful life until a late-night noise startles him. Investigating, he discovers an old acquaintance, Helga, in his living room.