Crimson Codex
Crimson Codex is a supporting character in Fate/Samurai Remnant. He is a sentient Western magical tome left behind as a legacy by Miyamoto Musashi. Floating through the air and speaking fluent human speech, he acts as a mentor in magecraft to Miyamoto Iori and considers himself a surrogate parent following Musashi's death. Possessing vast knowledge accumulated over centuries, he guides Iori through battles and aids him with advice on practical matters such as local spiritual grounds.
Overview
Crimson Codex is a supporting character in Fate/Samurai Remnant. He is a sentient Western magical tome left behind as a legacy by Miyamoto Musashi. Floating through the air and speaking fluent human speech, he acts as a mentor in magecraft to Miyamoto Iori and considers himself a surrogate parent following Musashi's death. Possessing vast knowledge accumulated over centuries, he guides Iori through battles and aids him with advice on practical matters such as local spiritual grounds.
Appearance
Crimson Codex appears as a leather-bound book that floats in midair. On its front cover, two jewel-like eyes are arranged vertically above a decaying, weathered mouth.
Personality
Crimson Codex possesses the disposition of a caring and lighthearted old man. Though wise and protective toward Miyamoto Iori as a surrogate father, he also displays a mischievous streak. He places high value on human connections and fate, encouraging others to cherish their bonds. He retains a boyish passion for grand engineering feats, becoming exceptionally excited upon seeing impressive machinery like a giant wooden horse.
Abilities
As a sentient Mystic Code, Crimson Codex can levitate freely and speak. He is highly knowledgeable in jewel magecraft, instructing Miyamoto Iori in fire-based spells such as Flame Snake. He contains an accurate map of Edo within himself and offers detailed advice regarding ley lines and workshop construction. Furthermore, his extensive memory allows him to deduce the true identities of certain Servants upon seeing them.
Background
Originating several centuries ago, Crimson Codex was formerly owned by Miyamoto Musashi. After her passing, he remained behind as part of her legacy and took on the role of teaching Miyamoto Iori magecraft. Accompanying Iori on his journey through Edo, he provides vital tactical and spiritual guidance. His long existence grants him familiarity with historic figures, occasionally allowing him to recognize legendary heroic spirits from his past memories.
Relationships
He serves as the teacher and self-proclaimed surrogate parent to Miyamoto Iori, who affectionately addresses him as an old man. During an encounter with Rogue Caster (Circe), he was outmatched by her ancient magic and subjected to a prank that temporarily gave his cover a pig's nose. As an item imbued with human-like intellect, he shares structural similarities with other sentient Mystic Codes such as the Kaleidosticks, Trimmaud, and Add.
Trivia
Because his name translates to red jewel and he operates as a self-aware magical item, fans often speculate on potential connections between him and Magical Ruby or her creator. Fans also frequently compare him to talking book characters from other notable video game franchises.