FMA Brotherhood Plot Hole: Why Can't Alchemy Regrow Ed's Limbs?

A significant world-building inconsistency in Fullmetal Alchemist: Brotherhood concerns why Edward Elric's lost limbs (right arm, left leg) are never restored through alchemy, despite the established capabilities of the system: **Medical alchemy exists and works**: Marcoh healed people in a remote village. The Rockbells practiced medical alchemy. Bio-alchemists can manipulate living tissue, heal wounds, and reshape bodies. Scar's brother extensively researched body reconstruction. **Chimera creation is arguably harder**: Shou Tucker fused a living human and dog into a speaking chimera. If you can merge two entirely different biological organisms into a functional hybrid, regrowing a hand from existing biological templates should be less complex, not more. **The body already regenerates**: Alchemists would just be accelerating and directing a process biology already handles — cell division, tissue growth, wound healing. Marcoh's healing must have involved tissue regeneration at some level. **Possible but weak defenses**: - "It's too complex" — Alchemists routinely do absurdly complex transmutations (chimeras, nationwide circles). - "It was Ed's toll from Truth" — Possibly the strongest argument thematically, but the show never explicitly states the loss is metaphysically locked. Ed eventually gets his arm back through another Gate exchange, suggesting it's not permanent. - "You'd need to create new living cells" — But medical alchemy already creates/heals tissue. **The real reason is narrative**: Ed needs automail because it's iconic, creates meaningful character limitations, and drives plot. The world-building doesn't fully justify it when you follow the internal logic of what medical alchemy can demonstrably accomplish.