Cornello

Father Cornello is a charlatan who poses as a priest of the Church of Leto in the small desert town of Reole in Eastern Amestris. As such, he devotes a great deal of time and effort building up a legion of followers in the town as a type of cult leader through the work of divine miracles. The Elric Brothers discover, soon after arriving in Reole, that Cornello's 'miracles' are nothing more than alchemy augmented by a Philosopher's Stone that the priest has in his possession and Cornello himself admits that his motivation for doing so is to create an army of religious fanatics large enough to overthrow the Amestrian government and place him as the country's ruler. Edward confronts and defeats Cornello (while revealing to the townspeople that the priest has been duping them), but during the struggle, the Philosopher's Stone is shown to be an imitation and inflicts Cornello with an alchemical rebound that deforms his hand. After being shunned by the village, Cornello rushes to Lust, who had given him the stone in the first place. As he has outlived his usefulness to the Homunculi, Lust kills him and the corpse is eaten by Gluttony, after which Cornello is imitated and effectively replaced by Envy.

During the 2009 anime, it is shown that despite being injured with a rebound, Cornello is able to use the stone's power to morph into a gigantic and monstrous form of himself. But in both the manga and 2003 anime, he is defeated in his normal form almost immediately after the rebound renders him practically useless.