Bronze-Link Manipulators

Coupled Reinforcement Mystic Code. A Mystic Code that Fiore designed herself. It takes over the role of her paralyzed legs. It consists of four prosthetic arms equipped to her back. It was forged using a special alloy that easily conducts mana and is possessed by four animal (dog) spirits, so while Fiore can move them according to her will, the arms also move automatically to protect their master.
Unlike the Volumen Hydrargyrum that Kayneth El-Melloi designed, its movement pattern memories are kept to a minimum. When too many movement patterns are recorded into it, it exceeds the thought process limit of the animal spirits. In other words, it is slightly inferior to Volumen Hydrargyrum in terms of attack power. In exchange, its defense—its function to protect its master fully uses the reflex speed of the animals, so it can't be broken through with a normal Mystic Code.
When she controls it herself, the mana burden is quite large, but when it's switched to auto-mode, the mana burden is lessened. It is best described as a Mystic Code whose defensive aspect is more strongly ironed out than its offense.
Incidentally, this is a secret to everyone besides Caules, but Fiore gave each arm the pet names Aster, Blanca, Comet and Wolf respectively.

Fate/Apocrypha material: Fate/Apocrypha Encylopedia