The Flame Alchemist and Hero of Ishval, Roy Mustang is the colonel of the Amestrian Military and a State Alchemist. Roy was one of the few to make it through the Ishvalan Civil War unscathed, though the atrocities committed in the great struggle are part of what drove his ambition to become the Fuhrer of Amestris.
His closest friends are Maes Hughes and Lieutenant Riza Hawkeye, the former of which was murdered by Envy after he discovered the Homunculi's plans. As a result of Hughes' death, the Colonel went on a vendetta to find the killer, culminating in a violent confrontation with Envy as Roy wreaked vengeance upon the murderous homunculus.
After Pride and Wrath forced him to open the portal and see the Truth, Roy was used as one of Father's sacrifices in his grand scheme to absorb all the souls in Amestris and swallow God. Roy was rendered blind as a result. After Father's plan was unraveled through the efforts of Van Hohenheim, Roy was one of those who took place in the final battle. Afterwards, he went on to become the Fuhrer and his vision was restored by a remaining Philosopher's Stone.
As the Flame Alchemist, Roy makes use of Ignition Cloth Gloves to create a spark when he snaps; by then manipulating the oxygen density in the air using alchemy, he can then generate flames. His flame alchemy ranges from great bursts and explosions to very precise and surgical fire.
If his special gloves are wet, however, he cannot create the sparks necessary to produce flames, hence being "useless on rainy days". Aside from these, he also knows the standard form of alchemy.