A Solo Servant summoned by the Moon Cell to act as SE.RA.PH’s system administrator.
He is given form as a technician to perform maintenance on SE.RA.PH, but after coming into contact with the harvester of worlds known as the Umbral Star, Archimedes becomes its devoted apostle.
When he interfaces with the once-sealed Ark of the Stars, he becomes corrupted by its influence.
He then begins preparations so that the Umbral Star can consume the Moon Cell once and for all.
Although he acts like a vassal of the Umbral Star, he has no intention of letting himself be controlled. For its part, the Umbral Star has no direct method to control Archimedes either.
If asked why he would work for the Umbral Star, Archimedes would reply with:
“No reason. I am simply bored of the civilizations of Earth. I want to know how the intelligence of other sentient life forms is constructed.”
In this story, he is the mastermind who awakens Altera’s deadliest form, the White Titan Sephyr.

Archimedes is introverted, stubborn, and active.
Reasonable and rational, he is the personification of order and individualism.
He is quite talkative, but while his tone is gentle, there is a fire behind his words.
He is a curious creature, both social and rational.
Archimedes believes that the world should be peaceful, and strives to ensure that it is, but he also places himself above this level of reasoning.
“Totalitarianism is the best method to achieve societal happiness. This is because it enables us to acquire resources more efficiently. This is how a system should be. Yes, indeed… All human beings, aside from myself, should work for the greater good.”
He approves of a society that is rational, but not necessarily because he dislikes conflict; rather, he thinks that it is necessary to sustain a society as a high productivity machine.
Archimedes believes that the solutions he seeks are paramount to everything else, and he has used any and every means to achieve his goals.
He despises the foolishness of humans. The weakness that prevents them from accepting reality for what it is because they prioritize their emotions. But his loathing is not directed at any particular individual, rather he hates the human way of life in general.
Archimedes hates the way humans cannot prosper without creating a “hideous” society, and is disappointed in people whose opinions are swayed by their emotions. Thus, it is rare for him to show his animosity in front of people.

Originally, he lived around c. 287 BC - c. 212 BC. Mathematician, engineer, and astronomer.
He was born to a line of artists, and took up astronomy as his father did before him.
At the point of his death c. 212 BC, he resided in the city of Syracuse, located on the eastern coast of current-day Sicily.
Archimedes’ famous achievements involve a range of geometrical theorems from “On the Equilibrium of Planes,” “On the Measurement of a Circle,” and “On the Sphere and the Cylinder,” as well as “Archimedes’ cattle problem (finding the integer value to Diophantine equations)”.
While his peers respected his talent, they also considered him rather strange.
He proudly lived in isolation far from Alexandria, the center of academic pursuits at the time, often only communicating by letter with other scholars. His pride and independent way of life forms the basis for his beliefs in Extella.
Most scholars of his era relished the act of uncovering new things through discussion itself, and treasured recognition just as much as discovery, basking in the praise of the citizens around them.
Archimedes had no such interest, and is said to have been fixated on the beauty and accuracy of his own theorems.

Archimedes was the cornerstone of Syracuse’s defenses, an outstanding mathematician, as well as a talented engineer.
The coastal city-state relied ”super weapons” devised by Archimedes far more than it did on ordinary soldiers.
Plutarch wrote in his Parallel Lives that Archimedes was related to King Hiero II, the ruler of Syracuse. It is easy to imagine how he ended up in the position of chief engineer tasked with the defense of the city-state. Archimedes was famous as an engineer throughout the land from early on. Ancient Greek historian Polybius, born c. 204 BC, wrote the following account in his Universal History some seventy years after Archimedes’ death:

“If you were to see his works, you would easily understand how the intelligence of a single human being can bring about astonishing achievements if they are given the opportunity. In truth, the Roman armies who had shown overwhelming might across both ground and sea were convinced that they would be able to conquer the city-state of Syracuse should just that single old man disappear. However, for as long as Archimedes was alive, and his methods of protecting Syracuse were in place, the Romans feared to even approach the city’s walls.”

Many of the defense mechanisms he invented effectively demolished a variety of would-be invaders.
However, in the year of c. 212 BC, Syracuse formed an alliance with Carthage during Carthage’s Second Punic War against the Romans, and so Syracuse and Rome became enemies.
Consequently, a Roman force led by the General Marcus Claudius Marcellus laid siege to the city.
Archimedes’ fortifications effectively repelled the invaders, but the city fell due to treachery, and Archimedes lost his life in the aftermath.
However, his story comes to an end after the siege, rather than during it.
Archimedes’ name was well known to the Romans, and the victorious General Marcellus sent out orders that the scholar was not to be harmed. According to the popular account given by Plutarch in his heroic tale Parallel Lives, Archimedes was deep in thought when the city was captured. A Roman soldier came to take custody of him, and commanded him to come along, but he declined. The soldier then flew into a rage and killed Archimedes with his sword.
(Plutarch himself notes that this story a mere rumor, and clarifies that there were other rumors as well, like one stating that Archimedes was killed because the soldier thought the technical drawings in his possession would be valuable spoils of war.)
It is said that Archimedes’ last words, uttered to the soldier who stopped him while he was drawing geometric configurations in the sand, were “μή μου τούς κύκλους τάραττε” meaning “Do not step on my figures / Do not disturb my circles!”
Despite those last words being well known, they are not noted in Parallel Lives, and their source remains a mystery.

I digress, but as a final bit of trivia: When Roman writer and politician Marcus Tullius Cicero was in Sicily c. 75 BC, he reported finding the tomb of Archimedes near the Agrigentine gate in Syracuse, clearly neglected and overgrown with bushes. It is said that the tomb contained a sculpture illustrating the late scholar’s favorite proof, consisting of a sphere and a cylinder of the same height and diameter. This was one of the greatest mathematical accomplishments of his life.

In the world of Fate, Archimedes lived his life as a man who could not see beauty in anything but the solutions he created within himself. Because of his great intellect and his flexible perspective, however, he was not ostracized from society.
Even though he was resigned to the fact that he was “different” from everyone around him, he was also socially adept and magnanimous.
His genius contributed greatly to the advancement of Syracuse. Other mathematicians of the time only pursued the “beauty of their theorems,” and had no interest in the way society should be.
And so Archimedes, who endeavored in very different fields of math and industry, could even be considered an aberration.
His dual nature is what led to his conflicting character as both self-absorbed, yet also in the service of people, working for others as an engineer.

After he becomes corrupted by the Umbral Star, his frustrations surface toward both his own failings and the foolish commoners, turning him aggressive.
Truth be told, he is in a constant state of anger.
He recalls every goal he failed to achieve in life.
He laments the unchanging nature of humanity.
Everything about himself from the bowels of his consciousness.
And so, he thinks nothing of deceiving and manipulating others.
As a matter of fact, he enjoys it. He had always thought that the only things that would move as he intended were his numbers, his creations. But after all this time, he has realized that even the world itself is merely a tool, one he can manipulate to his heart’s desire.
So he hides his aggressive nature with a smile, and finds joy in the way he can now draw fully upon all of his strengths to achieve his goals.

“Previously, I had only found joy in mathematics.”
“Troublingly enough, things are a bit different now. I have found some entertainment in my own life.”

One could even say that Archimedes has finally regained the innocence of his youth.
He can even smile at his enemies, as he considers everything to be “his own tool.”
He does not hate those who go against him. Even if his orders are resisted or he is betrayed, as long as the process that led to the result is logically correct, he is satisfied with the outcome.
What he truly dislikes and finds distasteful are opponents who have “strayed from logic.”
He loathes those who would not choose the correct answer when it’s right in front of them.
His mortal enemies are those who would rampage down the wrong path at full speed without a shred of reasoning.

Fate/EXTELLA material: Encyclopedia of Fate EXTELLA