Summary
One of the saddest tragedies inFullmetal Alchemisthappened to a little girl named Nina Tucker who was turned into a chimera by her own father and died soon afterward.Alphonse and Edward Elricwere there at the time, but there was nothing they could do to save her because they didn’t know anything about human chimera. That is why what happened to Nina remains to be one of the biggest regrets of their life.
That said, the Elric brothers gained a lot of knowledge by the end of the series. So could they save the other human chimeras with the information that they have gathered thus far? Can a human chimera transformation even be reversed in the first place?

What is A Human Chimera?
Before going any further, let’s talk about the definition of a human chimera first.In the world ofFullmetal Alchemist,a chimera is a creature that is born out of different animals that are alchemically fused together. A human chimera, therefore, is a human who is turned into a chimera by synthesizing other animals into their body.
The purpose of creating a chimera is usually to construct a new creature that can harness the great qualities of different animals, such as combining the tremendous raw physical power of a gorilla with the deathly jaw strength of a lion. Since it’s incredibly difficult to pinpoint a specific characteristic of an animal and combine it with another specific trait from different animals, synthesizing a chimera often leads to more failure than success. That is why there are not many alchemists who are willing to pursue this field.

The Human Chimeras In Fullmetal Alchemist
Excluding Nina, the majority of human chimera in the series can be divided into two camps. Some of them belong to Greed’s group, while others belong to Major Kimblee’s group. There are five human chimeras inGreed’s gang in Devil’s Nestand four are working under Major Kimblee. Every single one of them are former Amestrian soldier and all of them are the result of the military’s secret human chimera experimentation. However, only the four under Kimblee are still working in the military.
Although the human chimeras in Greed’s gang are leagues above simplehuman chimeras like poor Nina,the military still considers them as a failed product. The reason is even though they can retain their sanity and personality while fully using the abilities of the animals that are synthesized to their body, such as the gecko’s wall-crawling ability or the snake’s long and flexible limbs, they still have a deformed human-animal hybrid body.

The chimeras under Kimblee, on the other hand, can not only use their animalistic traits but also freely transform from regular human form to hybrid chimera form. That is why according to the Amestrian military, these four are the only successful human chimera ever created.
Can A Human Chimera Transformation Be Reversed?
So can a human chimera transformation be reversed? Can a human chimera return to being a regular human? Well, the answer is yes, at least in theory. As mentioned earlier, the Elric brothers learned a lot regardinghuman transmutationthroughout their journey. So by the end of the series, Edward and Alphonse have worked out some sort of theory on how to reverse the human chimera transformation.
According to alchemy, there are three major components to a human being, the physical body, the soul, and the spirit. The physical body is simply a string of chemical reactions. Given the right ingredients, every decent alchemist should be able to construct a lifeless human body. The soul, on the other hand, is the consciousness, the memory, and the personality of a human being. This can’t be synthesized, and once it’s gone, there’s no way to get it back. Lastly, the spirit is the thing that connects the body and the soul.
In the case of human chimera,the human soul inside the deformed body is relatively intact. So in theory, if an alchemist can extract the soul of a human chimera, store it in a temporary vessel (like Alphonse’s soul within the armor), and separate the human body from the animal, then the soul should be able to find its way back to the original body. Thus returning them to a regular human.
The main problem with this theory, however, is the spirit. There’s still lots of unknown information regarding the spirit. But once the brothers,or any other alchemist,can fully understand the matter regarding the spirit, then reversing a human chimera transformation should be possible.
This is pretty much what the brothers try to do by the end of the series. After all, they heavily regret their inability to act during the Nina tragedy. So they both decided to gather information from every corner of the world and help the remaining human chimeras to return to their original body, with Alphonse headed to the East and Edward headed to the West.
As a matter of fact, Alphonse’s bodyguards for this upcoming journey are none other than the two human chimeras under the late Major Kimblee, the human-toad/frogfish chimera named Jerso, and the human-razorback/hedgehog chimera named Zampano.
The series endedbefore we could get closure regarding this issue. But if there’s a chance for a sequel in the future, then it’s highly likely that the brothers would’ve figured out how to reverse the human chimera transformation.
Fullmetal Alchemistis available to stream onCrunchyroll.
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