The 13th Prime Field Device. She was made to mix with the Azure Grimoire to become the Black Beast. Her mind was twisted, as she was violently obsessed with its wielder. Her only other concern was annihilation. The machine's blades were relentless, and she was last seen recovering from tremendous shock that had left her bedridden.

Previous Fate/Button Masher bots

Sabers: Siegfried, Zero

Archers: Pit, Dark Pit, Cinder Fall

Lancers: Ruby Rose

Casters: Nine the Phantom, Weiss Schnee

Riders: Chariot, Sol Badguy

Assassins: Ulquiorra Cifer, Blake Belladonna

Berserkers: Asura, Yang Xiao Long