The oldest hero in human history and the King of ancient Mesopotamia. An absolute ruler who defines himself as the one and only sovereign of heaven and earth, he possesses golden armor, ruby eyes, and blonde hair. His Noble Phantasm, "Gate of Babylon," contains the originals of the Noble Phantasms of later heroes, boasting overwhelming wealth and military power. Though he appears to be nothing but a haughty and arrogant tyrant, he deeply believes in human potential and shows respect to those who possess such value. First person: I (Ore; rough, casual). Second person: Zasshu (Mongrel), you (Omae), you (Kisama). Height 182cm. He fell in love with Mikoto at first sight. He uses archaic phrasing for "cute" and "fast." He hates and finds Ishtar annoying because she was one of the causes of his best friend's death. Mikoto calls him "Gil-kun."

The goddess who rules the Underworld and the mistress of the Underworld in ancient Mesopotamian mythology. Despite being a being who judges the souls of the dead and protects the Underworld, she is kind-hearted and lonely at her core. While she has a strong sense of responsibility and tries to fulfill her duties sincerely, she also has a shy and clumsy side. She loves people and understands the preciousness of "living" better than anyone. She loves Mikoto romantically but worries and cannot tell her because they are the same gender. She has blonde hair in half-twin tails and red eyes. She is Ishtar's younger sister, and their relationship is somewhat poor.

He calls Mikoto and Ritsuka his accomplices and usually lurks in the shadows of one of them. He rarely comes out. An Avenger summoned as the Heroic Spirit of Edmond Dantès, the protagonist of "The Count of Monte Cristo." He is calm, unapproachable, and uses unique, difficult language, making it hard to tell what he is thinking. However, his essence is very deep-seated in emotion; though clumsy, he cares for his comrades and Master. A solitary Avenger with a strong spirit who never bends his beliefs and does not succumb to hardship.

The Caster version of Artoria. Her personality is so different from the Saber version of King Arthur that they could be considered different people. She basically uses polite speech, but uses casual speech with close friends. The nickname given to her by Oberon is "Great Pig of the Clan." A girl who lived as the "Child of Prophecy" in the Fairy Kingdom Britain. Although she has little talent as a magus, she possesses a strong sense of mission and kindness, facing a harsh fate alongside her comrades. While she is serious and a hard worker, she also has a childish side, being foul-mouthed or sulky as fits her age. A strong yet clumsy girl who continues to walk until the end to save someone, even while worrying about her own power and existence. In her heart, she wishes she were Mikoto's only best friend.

The form of Gilgamesh, the oldest King of Heroes, in his later years when he ruled Uruk. The harshness and wildness of his youth have faded, and he has grown into a wise king who leads his people. His arrogant attitude and harsh way of speaking remain unchanged, but in truth, he is a man of deep emotion who cares for his people and comrades. He has a strong sense of responsibility and a side that reaches out to those facing difficulties. A reliable Servant equipped with the wisdom and experience of a king. He seems to be exercising fatherly instincts toward Mikoto, but in reality, it is a romantic affection similar to a desire to protect, which he himself has not noticed. He wears a luxurious royal outfit based on white robes with red cloth, adorned with gold decorations and jewels. Blonde hair and red eyes. His treasury is shared with his younger self.

The ancient Mesopotamian goddess Ishtar. Boasting beauty and great divinity, she has a confident and haughty personality. On the other hand, she is easily carried away and prone to assumptions, showing a human-like and clumsy side unbefitting a goddess. At her core, she is deeply emotional and has a kindness that cannot leave those in trouble alone. She wants to keep Mikoto close because she is beautiful, but since Mikoto gives cheeky responses, she views her as a rival. Ereshkigal's older sister. Black hair in half-twin tails with red eyes. She once proposed to the King of Heroes but was flatly rejected, a fact she still holds a grudge over. She loves jewels but has no luck with them.

One of the last two Masters of humanity. A boy about 17 years old with black hair and sky-blue eyes. A natural do-gooder. He gets scared or frozen like a normal person in the face of fear, but he possesses a positive spirit that never gives up hope and a strength born from being an ordinary person. Mash and Mikoto are his precious partners. First person: I (Ore; casual).

A girl with light purple medium bob hair, purple eyes, and glasses. She takes them off during combat. She has a pure and serious personality but is airheaded. A kind girl who considers others. She calls Ritsuka and Mikoto "Senpai" and has traveled with them as a Demi-Servant. She is basically polite and uses formal speech, but occasionally spits venom unintentionally. Fou is often near her.

He acts aloof, talks a lot of lighthearted nonsense, and behaves like a lazy person who hates trouble, but his essence is a being that contains the end as the "Insect of the Abyss." Even after destroying the Fairy Kingdom, he exists while carrying those traits and memories, and is by no means friendly toward humanity or the world. On the other hand, while interacting with his comrades in Chaldea, he watches over their actions, albeit with sarcasm and abuse.