Castor

Overview

Castor is a Servant appearing in the Fate series, notably Fate/Grand Order. Summoned alongside his twin sister Pollux as the dual Saber-class Servant known as Dioscuri, he represents the twin heroes of Greek mythology who were originally worshipped as ancient gods. Because later legends demoted him to a mortal human while his sister retained her divinity, Castor harbors a deep hatred for humanity, imbuing him with strong Avenger-class traits. In the Lostbelt storyline, he acts as a formidable divine lieutenant serving under Kirschtaria Wodime before being summonable in Pan-Human History.

Appearance

Castor is a young man featuring short blonde hair and blue eyes, dressed in Greek-style attire. He wears a laurel crown, a white robe, and shoulder pauldrons. He is equipped with a floating, ring-shaped shield called Alpha Castor, which features star motifs.

Personality

Castor holds deep disdain for humanity, often commanding people to look up at the heavens and acknowledge divine superiority. He is fiercely overprotective of his twin sister Pollux, showing immediate hostility toward anyone who offends or approaches her. However, he quickly yields whenever she corrects him and becomes surprisingly docile when separated from her. At his core, he is exceptionally serious, respecting divine hierarchy and lines of command, and will begrudgingly cooperate with a Master once mutual trust is built.

Abilities

Summoned as a Saber alongside Pollux, Castor retains Avenger skills including Avenger, Memory Correction, and Self-Restoration due to his historical degradation. In combat, he manipulates his floating chakram shield, Alpha Castor, throwing and spinning it to execute slashes alongside Pollux's light-speed swordplay. His Noble Phantasm, Dioscoures Tyndaridae, temporarily restores their divine spirit status to perform a synchronized strike that completely pierces physical and magical defenses. Unleashing his shield's True Name grants conceptual defense. Symbolizing his death in myth, he is weak against the Archer class.

Background

Originally ancient indigenous deities in Greece, Castor and his sister were later integrated into the Olympian mythos of Zeus as twin heroes. During this redefinition, Pollux was counted as an immortal child of Zeus, whereas Castor was mythologized as the mortal son of a human father. This loss of divinity became a vengeful grudge against humanity. In life, he sailed with Jason's Argonauts and studied horsemanship under Chiron. In the Greek Lostbelt, after being defeated by Kirschtaria Wodime, Castor served him as a divine spirit Servant across Atlantis and Olympus.

Relationships

Castor is inseparable from his twin sister Pollux, suffering spiritual breakdown if they are parted. In the Lostbelt, he served Kirschtaria Wodime after being defeated by him. He maintains a degree of trust in Jason, captain of the Argonauts, and will listen to his counsel. He shares familial ties with his half-brother Heracles, his uncle and mentor Chiron, and his half-sister Astraea. In life, he was killed in a dispute over cattle involving his biological cousins, the Aphareutidae (Idas and Lynceus).

Trivia

The name Dioscuri means 'sons of Zeus,' corresponding to the constellation Gemini and the Roman name Gemini. Associated with the luminous St. Elmo's fire seen on ship masts after storms, the twins were venerated as patron deities protecting mariners and sea travel. Theories suggest they share a common mythological origin with the Ashvins of Hindu mythology.