Major Alex Louis Armstrong, the Strong Arm Alchemist, was born into an elite family of alchemists and has mastered his family's techniques. Members of his family have, in the past, filled the highest military and political positions in the state. He acquired his alchemy titles for his skill of using arm strength in his alchemy. All though he may look intimidating, he is really friendly and (overly)affectionate, and often stays behind or risks his life for the safety of others. He also has a tendency to show off techniques passed down to him to his enemies, and make them feel somewhat awkward during a battle. The scion of the illustrious Armstrong family, Alex is a remarkably caring commander and friend as well as an invaluably skilled ally to Colonel Roy Mustang and Edward Elric.
She has the power to control water. She is a homunculus that took the body of Trisha Elric (Ed and Al's mother).
The leader of a group of Ishvalan survivors, he has repeatedly cared for Scar when Scar was injured in Central. After the mercenary raids against the Ishabalan camp in Central he moves his group further south. He is never mentioned by name in the anime nor the manga, though he was identified as Rick and Leo's grandfather in the anime episode Marcoh's Notes.
"Karley is an Amestrian State Military officer stationed at Fort Briggs under the command of Major General Armstrong. As a primary communications officer for the fort, he is frequently seen toting a large radio transmitter or wired communications pack on his back while in transit and is often put in charge of relaying information and orders to Briggs troops in combat. Karley is first seen participating in Captain Buccaneer's mission to rescue the lost search party inside the tunnel created by the Homunculus Sloth and later appears as the head of communications during Major General Armstrong's role in the capture of Central Command." (Source: Full Metal Alchemist Wiki)
Lyra begins as an alchemist under the command of Lieutenant Yoki in Youswell with aspirations of becoming a State Alchemist. Lyra's alchemical attacks condense the moisture in the air and force it at high velocity toward her adversary. Her necklace bears a small transmutation circle. After being defeated by Edward in a battle, she seems to learn from her mistake in following Yoki and becomes the apprentice of Dante three years later in an effort to improve her already strong abilities and become an even greater alchemist. Dante, whose body was aging, performed a body switch with Lyra using the Philosopher's Stone and then proceeded to kill the original Lyra so that her secret would remain hidden. Edward later finds the remains of Dante's old body and assumes the homunculus Greed was responsible. (Source: Fullmetal Alchemist Wiki)
A member of a bandit group who hijacked a train headed towards Central City so that he could trade the safety of the passengers on board - most notably General Haruko - for the freedom of his group's leader. Originally a member of the military, he desired an Automail arm to increase his power. This use of automail for unnecessary procedure was prohibited by the State, and Bald was discharged and became an outlaw, seeking revenge on the military that disbarred him. His automail arm includes two gun barrels and a small knife blade. While hijacking the train, Bald was confronted by Edward, who disabled his arm and defeated the bandits, an exploit which won him permission to take the State Alchemist entry exam. He would later resurface in "Curse of the Crimson Elixir" inside the sewers of Eastern City, and then "Stray Rondo" to repeat the same crime, only to be put in jail yet again both times by the Elrics. In the manga, he's actually part of rebels who against Amestris, possibly from one of the southern bordering country which area had been taken by Amestris during the war. In the anime, the event actually is part of a flashback to before Edward became a State Alchemist. Defeating Bald allows the Elrics to take the State Alchemist examination after a grateful Hakuro refers them. In the manga, Edward is already a State Alchemist (and fifteen years old) and returning from Lior. After defeating Bald, Mustang refers Edward to Shou Tucker and his research when Edward wonders if it would be possible to alchemically construct himself new limbs.
A key character in the anime, the Exile was the one who originally instructed Scar’s brother in the ways of the Grand Arcanum, the Ishbalan version of alchemy. At the time of his introduction in the anime the Exile was living alone in the southern refugee camp after he had been banished from Ishbal by the Ishbalans for using alchemy. When Scar accidentally wandered into his hut he learned of his brother's training under the Exile, and sought to learn how to complete the Philosopher’s Stone from him. After Mustang and his men arrived looking for Scar, the Ishbalan refugees were rounded up with the intention of being transferred to state-run camps set up to house Ishbalan refugees; however, the military had to separate the Exile from his own people after they attacked him. As a result, he was set to be moved independently from the main group for his protection. When Ed and Al arrived in the camp and spoke with him he revealed that the Ishbalan people were once alchemists, practicing the Grand Arcanum to reshape the things that Ishbala had given them. It is implied that this was once a highly respected position in Ishbalan society; however, times changed and the practice of the Grand Arcanum gradually became a taboo, as it was felt to go against the teachings of Ishbala by reshaping the things that Ishabala had given the Ishbalans. During this conversation the Exile revealed that the only difference between the regular method of producing the Philosopher’s Stone and the Ishbalan method for producing the stone was the number of people who had to be transmuted into the stone. He was last seen at the end of the anime returning to Ishbal with the Ishbalans to help rebuild their country and culture.