Scar

The Scarred Man (傷の男, Kizu no Otoko), known more casually as "Scar" (スカー, Suka), is a nameless lone serial killer and revolutionary who targets State Alchemists for his own brand of lethal justice in accordance with the fundamental tenets of his religion and for the revenge of his slaughtered people. An Ishvalan survivor of the Ishval Civil War, Scar is so monikered by a large X-shaped scar on his forehead and sports a conspicuous and intricate alchemical tattoo on his right arm, which he uses as his murder weapon of choice.

As a former warrior of Ishval, Scar is quite adept at hand-to-hand combat, boasting significant strength, remarkable agility and reflexes and deceptive speed. Though the 2003 anime shows him as a young armed combatant during the war, in the manga he displays his abilities on the field by subduing a number of armed Amestrian soldiers using only melee tactics. Scar's killing spree throughout Amestris itself is proof of his skills, as he manages to murder ten State Alchemists (including Basque Gran, who had been hailed as a combat specialist) and is able to hold his own against combat-based alchemists like the Elric brothers and Alex Armstrong. In addition, Scar proves himself capable of taking down inhuman beasts such as chimeras and the Homunculi. More recently, he has shown himself capable of fighting more or less on par with Wrath, who is not only considered to be the second strongest Homunculus (just below Pride), but also one of the most dangerous adversaries in the series in general.

Scar is also reasonably intelligent, able to comprehend some more complex alchemical texts and concepts despite having never studied the craft and an adequate tactician capable of immediately identifying and assessing his opponents' weaknesses in combat.

While his physical prowess and intimidating figure are frightful in and of themselves, Scar's most dangerous element is his right arm, which is able to destroy anything with which it comes into contact by way of the intricate and arcane Transmutation Array tattooed thereupon. As a fundamentalist opponent of alchemy, Scar does not consider himself an alchemist in the traditional sense (having purposely avoided even its study), but the strain of alchemy that his arm itself allows him to produce is powerful, advanced and unique. As observed by those who have seen it in action and lived to tell the tale, Scar's method follows the cyclical flow of transmutation, but only takes into account the first two steps - comprehension and deconstruction. By "stopping at the second step", the physical structure of whatever he targets is broken down and not reshaped, essentially reducing it to formless debris. By applying this method to his victims, he destroys their internal systems (general organs in the manga, but the brain specifically in the 2003 anime version) instantly while circumventing both Human Transmutation and the Ishvalan stigma associated with giving new form to one of God's creations. Still, for all the serial killer's anti-alchemical posturing, the fact that he is unable to deconstruct an object whose composition he does not comprehend suggests that Scar does have a fair bit of alchemical knowledge and must actively identify, or at least make educated guesses at, the makeup of objects he wishes to destroy; despite his repeated assertion that the arm (and not himself) is the one performing alchemy, Scar is an amateur alchemist by practice.

The origin of the markings on Scar's arm differ somewhat between the manga and 2003 anime storylines of the series, but in both it was originally the right arm of Scar's older brother, transferred from one sibling to the other in an emergency procedure during the Ishval Civil War.