In the Fullmetal Alchemist anime series, Homunculi are artificially generated beings, retaining human physical form and mental capabilities. However, they lack a soul, and their existence is replaced and replicated, to some slight degree, with the material created from an innumerable amount of souls called “Philosopher’s Stones”.

Ruthless and determined, these beings serve as the principal villains of the Fullmetal Alchemist series. They are manipulative, pulling the strings from behind the scenes for much of history, and cutting them when they no longer serve a purpose.

General characteristics

Each of the seven Homunculi present in the series is named after one of the seven deadly sins of Gregory the Great: Lust, Gluttony, Envy, Pride, Sloth, Greed, and Wrath. As such, some of their personality and/or character traits are defined by the sin of which they are the embodiment.

They are cruel sociopaths, as one would expect of incarnations of sin, although not incapable of questioning their nature or the validity of their existence. All Homunculi bear the mark of the Ouroboros. Athough the location of the mark varies, it usually has something to do with their sin (i.e. Gluttony has one on his tongue).

Homunculi are the product of attempted human transmutation. On initial creation, Homunculi do not possess human features, but rather resemble beings of decay; for example, organ piles and bones jutting out at odd angles. By feeding on Red Stones, they gain human shape, specifically the appearance of the human who they are an attempted resurrection of, as well as regenerative and other special abilities. By consuming still more Red Stones, they can extend their lives indefinitely, though they are by no means immortal.

Due to their diet of the healing Red Stone, Homunculi are endowed with amazing regenerative abilities, to the point of allowing them to return from utter annihilation. Apart from their healing power, each Homunculus is gifted with a paranormal power, similar but innately different than alchemy, which manifests itself uniquely for each of the Homunculi.

Because they serve as an imitation of life, they are weakened by the presence of the real thing. When brought into close proximity with the remains of the person that was supposed to be resurrected, they are weakened (to the point of paralysis if too close). A homunculus can only be truly destroyed by killing them while they have no red stone in them, which can be induced by a Flanel array or performed naturally by killing the homunculus until it has exhausted its Red Stone and thus can no longer regenerate.

Homunculi are also unable to perform alchemy, as they lack souls which are the source of a persons ability to perform alchemy (a human soul contains part of the gate, and thus a source of personal alchemic power).

It should be noted that a homunculi’s personality is not contained in its brain or even its absent soul but rather in its Oroborus tattoo. If the tattoo is tampered with the homunculus can lose its personality and be reprogrammed.

Due to the realization that they are mere imitations of human life, most Homunculi pursue the dream of obtaining a soul. To this end, they incessantly seek to create the Philosopher’s Stone. As they are powered by incomplete Philosopher’s Stones, they seek the power of the complete stone, and one who would grant them their one wish.

Dialogue among some of the Homunculi also indicate that there were previous incarnations of such Homunculi as Lust, Wrath and Sloth. For example, Envy tells Greed that the seven Homunculi have finally assembled “for the first time in a long time” - meaning that those Homunculi, all of whom have been created within the last ten years or so, must be new incarnations of previously created Homunculi with those names. Also, Lust tells Greed that she is the “new Lust”.

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