His True Name is the Phantom of the Opera, a mysterious masked killer who appeared in the 19th century novel set of the same name as the aforementioned Servant, likely having been the base model for said novel at the time and perhaps was an actual person in life named Erik.
Powers and Stats
Tier: 6-C. Higher with Christine, Christine
Name: Name: Assassin, “Phantom of the Opera”, "Erik"
Origin: Fate/Grand Order
Classification: Assassin-class Servant
Powers and Abilities: Superhuman Physical Characteristics, Skilled claw user, Mind Manipulation (Can charm women with his voice), Invisibility and Stealth Mastery with Presence Concealment (Presence Concealment users with B-rank or higher are capable of rendering themselves invisible by erasing their presence, making themselves difficult to detect against Magi and even Servants unless they attack) and Servant Physiology
Attack Potency: Island level (Is exceptionally strong as an Assassin-class Servant that is also willing to go into melee combat, possessing B-rank strength and should also at least be much stronger than a more recent Servant like Archer. Fought against Mash, Jeanne d’Arc, Marie Antoinette, and Amadeus Mozart in Orleans). Higher with Christine, Christine (Is a B+ rank Anti-Army Noble Phantasm, making it equal to Gáe Bolg’s Anti-Army function)
Speed: Massively Hypersonic (Has A-rank agility, enabling Phantom to keep up with most Servants in combat. Kept up with Mash, Jeanne d’Arc, Marie, and Mozart)
Lifting Strength: At least Superhuman (Even the weakest Servants are stronger than the strongest humans)
Striking Strength: Island Class
Durability: Island level
Stamina: High (Other Servants can fight endlessly for days without rest)
Standard Equipment: His claws
Intelligence: Phantom normally appears and behaves as a calm and gentleman-like man while singing his voice out in conversations with others, appearing as a rather comprehensive man and able to be approached and converse with. However, this is all but a facade to hide away his sorrow and guilt as well as being an actual insane and cruel-hearted man that will slaughter down anyone if it is for the sake of his purpose for his “Diva” Christine and to try and put up his act as a gentleman. Regardless, Phantom is also shown as a capable Servant in combat able to use the claws on his hands as weapons to fight his enemies with and even use his singing voice in conjunction with his Noble Phantasm to cause tremendous damage.
Weaknesses: Cannot attack while in Spirit Form.
Christine Christine: Surely My Love Song Shall Resound Even Through Hell: The Noble Phantasm of Phantom, the sublimation of the corpses of his former victims taking on the form of a gigantic pipe organ instrument. By playing the gigantic instrument and matching the musical tunes with his singing voice, Phantom can send out large-scale waves of magic that scatter across and damage the environment and his enemies while he himself, its performer, will remain unscathed.
Presence Concealment: The ability to erase one's presence and become difficult to detect through mundane or magical means. Phantom’s ranking of A allows him to erase his presence nigh completely and spy enemies and prepare for an attack, but the skill's efficiency will drop the moment he starts to take them.
Alluring Nightingale: A skill possessed by those with naturally beautiful voices, which they can use to charm others as a declaration of their position of authority. Against women, this makes Phantom’s words alluring, allowing him to easily charm others, but it can be negated by Magic Resistance or resisted by those with a strong enough will.
Innocent Monster: An attribute possessed by Servants whose true history and existence have been distorted by the monstrous reputations and gossips they accrued across the course of their life and thereafter, without concern for the actual person's will or appearance. As a result, their appearance, abilities, and natures are modified to conform to these distortions. In Assassin’s case, having been the model for “The Phantom of the Opera” novel character, he has received the face and influence of said novel character. As a result, his arms and face becoming that of a grotesque monster. Were he to remove his white gloves, claws bigger and sharper than large knives are stretched out and will become exposed out in the open.
Mental Pollution: A distorted mentality that shuts out mental interference, at the cost of it being near impossible to come to terms or an understanding with Phantom. Phantom’s A-rank allows him to potentially shunt off any kinds of attempts to affect his mind.