Scar's Brother
Scars Brother giving up his life and arm to save Scars after he had been gravely wounded. Just like Scar his real name has never been revealed.
Spoilers:
In the 2009 anime, his research was what lead to a transmutation circle that was used against Homunculus; it was used to negate Homunculus control of
In the 2003 anime, he created Lust during a failed human transmutation, while attempting to bring back his lover.
