Edward & Alphonse vs. Scar
SPOILER!
Open →
Episode 14 · Central · Result: the brothers discover how badly outmatched they are
Scar attacks the Elrics as State Alchemists and tears through Edward's automail before either brother understands the full mechanism of his right arm.
The Breakdown
Scar does not need a flashy exchange of techniques. He analyzes the structure he touches and stops the alchemical process at destruction. The fight works because Ed's normal improvisation suddenly has no time to become clever: contact itself can end the battle.
WHY IT MATTERS:
This is the moment Scar stops being a rumor attached to dead State Alchemists and becomes Edward's personal evidence that the title he fought to earn has made him somebody else's legitimate target.
Edward vs. the Slicer Brothers
SPOILER!
Open →
Episodes 19–20 · Laboratory 5 · Result: Ed survives two souls in one armor
Edward enters Lab 5 expecting guards and finds an alchemical variation of his own brother instead: two convicted killers bound into a single suit of armor.
The Breakdown
The fight becomes a problem of blood seals rather than conventional anatomy. Destroying the armor is not enough, and discovering two separate souls forces Ed to rethink how reproducible Al's condition may be.
WHY IT MATTERS:
The battle turns soul binding from the desperate miracle Ed performed once into technology other people have learned to weaponize.
Edward vs. Greed
SPOILER!
Open →
Episode 34 · Dante's mansion · Result: Edward kills a Homunculus for the first time
Greed's Ultimate Shield initially makes Edward's attacks useless. Edward eventually realizes the shield is carbon-based and changes its structure through alchemy, creating an opening.
The Breakdown
Ed wins by understanding the material instead of trying to overpower it. The more important lesson comes immediately afterward: Greed reveals the weakness created by a Homunculus's connection to the remains of the person it resembles.
WHY IT MATTERS:
The fight gives Edward both a kill he did not emotionally expect and the rule he will later need against Sloth.
Edward vs. Sloth
SPOILER!
Open →
Episodes 46–47 · Result: Ed destroys the Homunculus created from Trisha
Sloth can turn her body into water and repeatedly uses Trisha's face against the brothers emotionally as much as physically.
Edward ultimately uses the remains connected to their mother to weaken Sloth and forces himself to finish the fight.
The Breakdown
The mechanics and the character problem are the same thing. The object capable of weakening Sloth is proof that Trisha died and that the being standing in front of Edward is somebody else.
WHY IT MATTERS:
Winning requires Ed to stop treating resemblance as resurrection. He cannot undo the original human transmutation until he accepts what it actually created.
Edward vs. Envy
SPOILER!
Open →
Episode 50 · Result: Envy turns family history into the opening
Edward can fight Envy's transformations until Envy reveals the face connected to Hohenheim's dead son and the 2003 anime's hidden family history.
The Breakdown
The decisive move is emotional rather than technical. Edward hesitates when the fight stops looking like hero versus Homunculus and suddenly looks like something his father created through the same forbidden grief that created Sloth and Wrath.
WHY IT MATTERS:
Envy's hatred of Edward is finally exposed as personal. The Homunculus conspiracy and the Elric family story become the same problem at the worst possible moment.