The Tringham Brothers
Russell & Fletcher · Xenotime
Russell and Fletcher Tringham impersonate the Elric brothers in Xenotime while pursuing their father Nash's research into Red Water.
The story is anime-original, but it matters beyond the gag of somebody stealing Ed's name. Xenotime introduces a community already being poisoned by the pursuit of a shortcut to the Philosopher's Stone.
Why it matters
The brothers meet an alternate version of themselves: two sons inheriting dangerous alchemy from an absent father and trying to decide what parts of that legacy are worth continuing.
Majhal
Soul-binding · Rose oil dolls
Majhal is an early anime-original alchemist who cannot accept the death of Karin and tries to preserve his idea of her through soul-binding and dolls.
He is not important because he returns later. He matters because episode 4 establishes a pattern the entire 2003 series will keep revisiting: alchemy becomes monstrous when grief is treated as a technical problem that can be solved if the alchemist refuses reality hard enough.
Why it matters
Majhal is a miniature version of the brothers' original sin before the larger mythology has even been explained.
Lujon & Fossil Ware Disease
Village of Fools · Lust
Lujon is a doctor trying to save a village from Fossil Disease when Lust offers him the apparent miracle of a Red Stone.
His story matters because Lust recognizes him. The episode gives the audience one of the earliest signs that a Homunculus can carry emotional residue from the human whose failed transmutation created it.
Why it matters
Lujon turns a side story into evidence about Lust. The person manipulating him is also being manipulated by memories she does not fully understand.
Frank Archer
SPOILER!
Military · Cyborg Gatling
Frank Archer is the military officer who treats every crisis as an opportunity to expand the State's control. Where Mustang carries guilt from Ishbal, Archer sees the same machinery and wants more of it.
After being catastrophically injured, he returns as a weaponized cyborg during the final conflict.
Why it matters
Archer is 2003 FMA making the military metaphor literal: the State takes a damaged human body and converts what remains into ordnance.
Wrath (2003)
SPOILER!
Izumi's failed child · Gate remnant
Wrath is the result of Izumi Curtis's failed attempt to bring back her dead child. He survives within the Gate and later emerges carrying Edward's missing arm and leg.
That makes his body a collision of two different human-transmutation failures: Izumi's grief created him, while Ed's toll helped complete the form he eventually uses.
Why it matters
Wrath forces Izumi and Edward to look at consequences they would rather classify as past mistakes. In 2003, the Gate does not keep those mistakes politely on the other side.
Sloth (2003)
SPOILER!
Trisha Elric Homunculus
Sloth is the Homunculus born from Edward and Alphonse's attempt to recreate Trisha. She wears their mother's face without being their mother, and the resemblance is exactly what makes confronting her so difficult.
Sloth herself wants freedom from the emotional residue attached to that face, even if that means killing the brothers who keep awakening it.
Why it matters
The brothers' first transmutation finally becomes somebody who can answer back. Sloth turns "we failed to bring Mom back" into a much crueler question: what responsibility do Ed and Al have toward the life their failure created?
