Martel

Martel (also spelled Marta) was a human chimera combined with snake. She was one of Greed's henchmen. She had the ability to stretch and twist her limbs.

Background
It is implied in the 2003 anime that Martel was a soldier in Ishval Civil War, though the manga states that she was critically wounded by a land mine in the recent Southern border war with Aerugo. She stepped on a mine and was taken to an army lab. There, she was combined with a snake. She escaped from there along with her friends Roa and Dolcetto.

Manga
In the manga Martel is first encountered in Dublith. She aids significantly in the capture of Alphonse Elric by getting inside his armor and stretching her limbs to impede his movements. In the raid on Devil's Nest she stays in Al's armor and survives the massacre. However when Greed, Martel, Roa, Dolcetto and Al try to escape through the sewer system, Führer King Bradley arrives to stop them. Roa and Dolcetto are killed almost immediately and Greed is defeated by Bradley. When Martel tries to kill the Führer for the murder of her friends, Bradley stabs her through Al's armor, killing her.

Anime
In anime Martel's role is slightly bigger as she survives the Devils Nest attack and Follows Ed and Al to eastern Amestris. She spies on Führer and Kimblee as they plan to destroy Lior. Martel finds out that Bradley is actually Homunculus and tries to escape. Bradley follows and kills her but not before she tells Al the truth about Bradley.