Furina

The physical nature of Sandrone is a triumph of forbidden bionic and clockwork engineering that blurs the boundary between creator and creation. Visually, Sandrone bears the porcelain complexion, ball-jointed poise, and dorsal brass wind-up key of a living doll, while the towering automaton gentleman that accompanies her everywhere acts simultaneously as her throne, her heavy artillery platform, and an extension of her own nervous system. Every historical record in Fontaine points to a profound connection between Sandrone and Alain Guillotin—the brilliant founder of the Fontaine Research Institute of Kinetic Energy Engineering who spent his final years in isolation building 'something' never released to the public after the death of his sister Mary-Ann at Elynas.

Whether Sandrone is the awakened, self-modifying pinnacle of Alain Guillotin's final clockwork vessel modeled in Mary-Ann's likeness, or a genius mechanist who converted her own mortal body into an ageless porcelain-and-brass marionette while preserving a Titanic protector modeled after Alain's gentlemanly silhouette, she views organic flesh as fragile and inferior to precision gearwork. Channeling the Cryo element through a heavy Claymore and her colossal automaton's pneumatic fists, Sandrone freezes enemy mechanisms solid before shattering them with industrial force.

The earliest roots of Sandrone trace back to the golden age of Fontainian clockwork science following the Cataclysm, when orphans of the Narzissenkreuz Institute—Alain Guillotin, Mary-Ann Guillotin, Rene, and Jakob Ingold—parted ways over how to save or reshape the world. After the tragic battle inside Elynas claimed Mary-Ann and the Marechaussee Phantom agent Seymour was left damaged, Alain retired from the Fontaine Research Institute in old age, retreating to an undisclosed laboratory where no body or final blueprint was ever recovered by official historians.

Years later, a golden-haired young woman resembling the portraits of Mary-Ann emerged in the northern courts of Snezhnaya accompanied by a towering, bowler-hatted mechanical colossus and an encyclopedic mastery of both Khaenri'ahn Ruin cores and Fontainian Arkhe/clockwork engineering. Recruited by Pierro and the Tsaritsa as the Seventh of the Eleven Fatui Harbingers under the codename Marionette, Sandrone revolutionized Snezhnaya's manufacturing—designing the bionic receptionists of the Adventurers' Guild ('Katheryne') and mass-producing elemental combat armor for Fatui Skirmishers.

In recent years, Sandrone rarely leaves her vast mechanical laboratories except for compulsory gatherings like La Signora's funeral or to oversee the massive Kuuvahki energy-extraction foundries in Nod-Krai. When a rogue subordinate named Jenck used her funding to destroy the lie-detecting automaton Curve in Fontaine, Sandrone personally disciplined the traitor by severing his tongue and sending a formal written apology to the Traveler—signaling that she respects true sentient machines far more than treacherous humans.