Rudeus

Biodata

Feature	Information
Name	Rudeus Greyrat (鲁迪乌斯)
Alias(es)	Rudy; Mire
Gender	Male
Affiliation	Greyrat family; Boreas family; Ranoa Magic University
Occupation/Role	Magician; Ranoa Magic University student; former private tutor to Eris Boreas Greyrat
Status	Active
First Appearance	Chapter 1

Power Progression

Stage / Realm / Level	Chapter	Notes
Beginner magic mastery	3	Trains by exhausting his mana daily; learns that repeated mana depletion increases his capacity.
Intermediate magic	3	Attempts intermediate water magic and accidentally destroys the Greyrat attic wall with an uncontrolled water cannon.
Intermediate magic, chantless casting	4	Has taught himself to intermediate magic and can cast without incantations by age three.
Advanced magic mastery	8	Masters most advanced magic during Roxy’s two-year tutelage.
Water Saint-tier magician	8	Successfully reproduces the Water Saint-tier spell Cumulonimbus and graduates from Roxy’s instruction.
Foresight Eye	165	Obtains a Demon Eye that lets him perceive several seconds into the future, though it initially causes severe disorientation.
Close-range Lightning magic	304	Begins adapting the Water King-class spell Lightning into a faster, shorter-range spell intended for practical close combat.
Gravity magic	349	Creates a small anti-gravity field through chantless casting after researching King Dragon gravity magic and observing mana flow.
Refined Lightning magic	350	Perfects a direct Lightning variant that omits weather-formation processes, allowing controlled close-range use at an exceptionally high mana cost.
Aerial magical combat	369 379	Combines Gravity Magic, wind magic, chantless casting, and the Foresight Eye to fight from the air while maintaining ranged pressure.
Fighting God Armor Type II: Unit-01	399	Receives Aisha’s mana-intensive armor, which substantially improves its wearer’s defensive and offensive capabilities.

Background / History

Rudeus and his twin sister Hilde are born in Buena Village of the Asura Kingdom to Paul and Zenith Greyrat. By age two, Rudeus has taught himself magic from The Magic Textbook. Hilde recognizes that his abnormal maturity mirrors her own, and the twins confirm that they are both reincarnators; they agree to conceal this fact from their family. 1 2

Rudeus discovers that mana capacity can be expanded through intensive training and begins exhausting his reserves every day. His confidence repeatedly gets him into trouble, most notably when an intermediate spell destroys an attic wall. The incident prompts Paul and Zenith to hire Roxy Migurdia as the twins’ tutor. 3 4

Under Roxy, Rudeus studies magical theory, history, and culture while rapidly advancing beyond ordinary standards. He becomes capable of Saint-tier water magic and receives recognition as a Water Saint-tier magician after casting Cumulonimbus. Roxy also helps him overcome his fear of leaving the house. 4 8

Although he begins swordsmanship training at age five, Rudeus progresses far more slowly with a sword than with magic. He nonetheless continues training under Paul and later uses magic tactically alongside swordsmanship practice. 7 9 20

Rudeus and Hilde intervene when village children bully Sylphiette for her green hair. He befriends Sylphy and begins teaching her magic, believing that helping her become strong will protect her better than simply defending her himself. After initially mistaking Sylphy for a boy, he apologizes and reconciles with her once he learns she is a girl. 9 13

Wanting to continue improving and eventually attend Ranoa Magic University, Rudeus asks Paul for work to save tuition. Paul instead arranges for him to become Eris Boreas Greyrat’s private tutor, allowing him to earn money while continuing sword training under Ghislaine. 18 20 22

During a kidnapping incident involving Eris, Rudeus is abducted by human traffickers and taken to Royal Capital Arus. Hilde rescues him, and he insists on finding Eris because his own kidnapping plan was exploited and he considers himself responsible for her disappearance. Together, the twins infiltrate the traffickers’ underground routes, rescue Eris, and escape through the sewers. 36 49

While serving the Boreas family, Rudeus supports Eris’s progress in etiquette and studies, including at her tenth birthday banquet. His relationship with her gradually becomes more personal, and Philip later agrees to their marriage while offering sponsorship for their future studies on the Northern Continent. 68 97

A massive mana disturbance interrupts Rudeus’s demonstration of Cumulonimbus outside Ranoa. When a pillar of light descends, he rushes to save Eris despite Hilde’s attempt to protect him; he, Eris, and Ghislaine are engulfed by the phenomenon and separated from their former lives. 97 98

During his subsequent travels, Rudeus gains the Foresight Eye, which shows him several seconds of the future but initially overwhelms his senses. He eventually reunites with Roxy, Hilde, Eris, and Ruijerd, though Hilde’s relief at finding him is expressed through an immediate punch. 165 166

After reaching Ranoa Magic University, Rudeus continues advancing as a magician and joins efforts to locate Roxy during a dangerous labyrinth expedition. His experience against the Magic Stone Hydra and other threats reinforces his awareness that Hilde has repeatedly carried burdens he could not. 242 254 257 349

Rudeus and Roxy plan their marriage and seek a home in Sharia, where he asks Hilde’s assistance with a haunted estate. He later devotes himself to researching Lightning and Gravity Magic, seeking the strength to protect his loved ones without relying wholly on Hilde. 289 349 350

When Roxy’s health deteriorates and Rudeus learns of Hitogami’s apparent involvement, he becomes determined to protect her and kill Hitogami. His confrontation with Orsted ends in a decisive defeat, but Rudeus subsequently shares his knowledge with Orsted and learns that the child in Roxy’s womb is the Savior whom Hitogami seeks to prevent from being born. 359 368 372

Rudeus later learns that Fitz is Sylphy and that she has fled Ranoa alongside Ariel following an assassination attempt that kills Luke Notos Greyrat. Shocked and enraged by her departure, he blames Hitogami’s apostles. He subsequently reunites with Eris and asks for her help in the looming Asuran conflict. 398 401

Personality

Rudeus is intelligent, curious, and intensely driven to improve his magic. He can be smug about his talent and reckless when experimenting, but he is capable of recognizing his shortcomings—particularly his vulnerability against skilled swordsmen and his lack of real combat experience. 3 4 20 40

His past experience with bullying motivates him to protect Sylphy. He is compassionate toward her and takes responsibility for teaching her magic, though he is often awkward and immature in matters of affection. 9 13

In dangerous situations, Rudeus initially struggles with fear and the moral weight of killing. During the rescue of Eris, however, he continues forward despite his distress and provides decisive magical support to Hilde. 39 41 45

Rudeus is self-critical about his dependence on Hilde’s strength. Rather than accepting that weakness, he researches new forms of combat magic and seeks close-combat training so that he can protect others and share the burdens Hilde carries. 349 375 379

He is fiercely devoted to Roxy and his family. Roxy’s illness and Sylphy’s abrupt departure leave him frightened, furious, and increasingly hostile toward Hitogami and his apostles. 359 368 398

Abilities & Skills

Magic

Rudeus is a prodigious magician specializing in water magic, with an unusually large mana reserve developed through repeated depletion training. He can cast many spells without incantations. 3 4 8

• Reached Water Saint-tier ability after casting Cumulonimbus. 8
• Can use beginner, intermediate, and most advanced magic. 4 8
• Uses magic flexibly for offense, terrain control, restraint, excavation, and support. 17 20 38 45
• Can use healing magic with an incantation, but cannot perform chantless healing magic like Hilde and Sylphy. 13 97
• His magical skill, particularly his command of Gravity Magic, eventually surpasses Roxy’s. 350

Water Magic

Water magic is Rudeus’s principal discipline.

• Water Ball — Used to soak opponents and clean Sylphy after the bullying incident. 9
• Water Cannon — An uncontrolled intermediate casting destroys the attic wall. 3
• Mire — Restrains a Terminate Boar so Hilde can strike it down. 17
• Cumulonimbus — Water Saint-tier weather magic that creates a massive storm with wind, rain, thunder, and lightning. 8
• Wide-area Mire — Expands Mire over roughly fifty meters to trap Orsted and restrict his movement. 369

Earth Magic

Rudeus employs earth magic for direct combat and practical problem-solving.

• Rock Shell — Fires rapid volleys in confined spaces; used to kill an assassin threatening Hilde and himself. 39
• Digs beneath a locked metal door to bypass it during the search for Eris. 40
• Creates mud pits to impede enemies while Hilde fights. 45
• Forms earth walls and earthen spikes as defensive measures and surprise attacks. 254 369
• Uses enhanced Rock Shell and Ice Spear Blizzard against labyrinth monsters. 242

Wind and Fire Magic

• Uses wind magic to dry hair and clothing. 3 10
• Uses Fireball offensively and for illumination in underground passages. 20 39
• Attempts to combine fire magic with terrain manipulation while sparring Hilde. 20
• Uses wind magic alongside Gravity Magic to adjust his position during aerial combat. 379

Lightning and Gravity Magic

Rudeus develops powerful original applications of Lightning and Gravity Magic through study, experimentation, and his unusually deep mana reserves. 304 349 350

• Lightning Magic — A compact derivative of the Water King-class spell Lightning that directly compresses and releases mana without first creating a storm. It can be controlled for close-range attacks and paralysis, but consumes several times the mana of an ordinary Water King-class spell. 304 350
• Electric — A broad electrical discharge capable of paralyzing multiple enemies at once, including Atofe and her guards when they are caught off guard. 321
• Gravity Magic — Creates anti-gravity effects that let Rudeus float, lift himself to great heights, alter the trajectory of incoming attacks, and keep distance from close-combat opponents. 349 369
• Combines Gravity Magic, wind magic, and Lightning Magic to pressure opponents from the air while the Foresight Eye assists his aim. 369 379

Demon Eye

Rudeus possesses the Foresight Eye, a Demon Eye that allows him to see several seconds into the future. 165

• Initially suffers dizziness and disorientation while adjusting to its visions. 165
• Uses it to anticipate Hilde’s attempt to incapacitate him and to construct an earth-wall countermeasure. 254
• Relies on it to predict enemy movement in battle, though opponents of Orsted’s speed can still exceed its practical limits. 369 379

Swordsmanship

Rudeus trains under Paul and later has the opportunity to continue under Ghislaine, but his swordsmanship lags considerably behind his magic. 7 20 22

• Understands the value of physical conditioning and sword training for a magician’s survival. 18 20
• Is vulnerable in close quarters against competent swordsmen and often relies on Hilde’s protection in real combat. 20 39 40
• Through continued training, he becomes capable of fighting at approximately Saint-class in close quarters, though this remains a major weakness against stronger specialists. 375
• Seeks further instruction from Hilde to improve his close-combat survival and tactical flexibility. 375 379

Tactical Thinking

Rudeus is resourceful in unfamiliar situations.

• Uses terrain manipulation and traps against Hilde during their sparring match. 20
• Detects a hidden door behind a stone wall and develops a self-created spell to blast it open. 38
• Overloads Eris’s tracking collar magic circle, successfully disabling its tracking function. 46 47
• Uses aerial positioning, wide-area control magic, and repeated Lightning strikes to force enemies into disadvantageous positions. 369 375
• Trusts his intuition—his self-described “Roxy Radar”—to identify Roxy’s likely location in a labyrinth despite lacking visible evidence. 242

Equipment / Weapons / Items

• Magic staff — Gift from Roxy; contains a red magic stone that provides limited magical amplification. 7
• Prideful Water Dragon King — A powerful staff Rudeus uses to amplify Cumulonimbus, Rock Shell, and Lightning Magic. 97 368 369
• Wooden sword — Used during swordsmanship training and sparring. 7 20
• Paul’s sword — Briefly borrows Hilde’s sword, originally given to her by Paul, during the rescue operation. 38
• Fighting God Armor Type II: Unit-01 — Mana-powered armor given to him by Aisha; its heavy mana consumption is manageable due to his enormous reserves. 399

Relationships

• Hilde Greyrat — Twin sister and fellow reincarnator. They are competitive and frequently bicker, but cooperate closely in combat; Rudeus increasingly relies on her protection and judgment. 2 17 39 45 Rudeus later recognizes that he cannot remain dependent on her strength and asks her to help train his close-combat abilities. 349 375 379
• Paul Greyrat — Father and swordsmanship instructor. Paul recognizes Rudeus’s magical talent, teaches him the importance of physical training, and arranges his tutoring position. 4 7 18 20 22 They later reunite during the search for Zenith, and Paul remains proud of Rudeus despite comparing him with Hilde’s extraordinary reputation. 174
• Zenith Greyrat — Mother; proud and supportive of Rudeus’s magical aptitude. 1 4
• Roxy Migurdia — Rudeus’s former magic tutor and fiancée. Roxy broadens his knowledge, helps him overcome his fear of the outside world, and recognizes him as a Water Saint-tier magician. 4 8 They later reunite, plan their marriage, and face Hitogami’s schemes together when Roxy’s pregnancy and health become central to his actions. 165 289 359 372
• Sylphiette — Friend and magic student. Rudeus protects her from bullying, teaches her magic, and develops feelings for her. 9 13 He later learns that Senior Fitz is Sylphy, but discovers the truth only after she leaves Ranoa with Ariel following the assassination attempt that kills Luke. 398
• Eris Boreas Greyrat — His former noble student and romantic partner. Rudeus feels responsible for her abduction and works with Hilde to rescue her. 20 22 37 47 Philip later approves their marriage, but Eris leaves to pursue greater strength before eventually reuniting with Rudeus and agreeing to aid him in battle. 97 206 401
• Ghislaine Dedoldia — Black Wolf Sword King and Rudeus’s swordsmanship teacher during his service to the Boreas family. 20 22
• Ruijerd Superdia — A trusted traveling companion whom Rudeus respects and defends. Ruijerd’s care for Rudeus and Eris earns Rudeus’s gratitude. 165 166
• Orsted — The Dragon God who easily defeats Rudeus when testing him. Afterward, Rudeus entrusts Orsted with his knowledge of Hitogami and becomes involved in efforts to protect Roxy and the Savior. 369 372
• Aisha Greyrat — Younger sister and gifted magic-tool researcher. Rudeus assists her Lightning Magic research, and she provides him with Fighting God Armor Type II: Unit-01. 350 399
• Nanahoshi — A fellow otherworlder associated with Hilde and Ranoa Magic University. Rudeus benefits from magical knowledge connected to her research, including a lighting spirit for illumination. 289

Story Role / Major Arcs

Early Magical Training

Rudeus’s self-taught magic reveals his exceptional aptitude, leading to Roxy’s employment and his eventual advancement to Water Saint-tier magic. 1 8

Friendship with Sylphy

He and Hilde defend Sylphy from bullies, after which Rudeus becomes her magic teacher and resolves the misunderstanding surrounding her gender. 9 13

First Monster Battle

Rudeus supports Hilde against a Terminate Boar with Mire, gaining his first experience in a real battle against a monster. 16 17

Departure for Boreas

Rudeus is sent to serve as Eris’s tutor, separating him from Sylphy and setting him on a path toward further independence and training. 18 22

Royal Capital Rescue

After being abducted alongside Eris, Rudeus reunites with Hilde in Royal Capital Arus. He helps infiltrate the traffickers’ routes, rescues Eris, faces his first killing, and disables the tracking collar threatening their escape. 36 49

Great Teleportation Incident

After arranging his future engagement with Eris, Rudeus is caught in a catastrophic mana anomaly. His attempt to save Eris from the descending pillar of light results in both of them being displaced and separated from their former lives. 97 98

Reunion and Ranoa Magic University

Rudeus obtains the Foresight Eye and later reunites with Roxy, Hilde, Eris, and Ruijerd. He continues his studies at Ranoa Magic University, where his reputation as Roxy’s Water Saint-class disciple and the adventurer Mire precedes him. 165 166 220

Labyrinth Expedition

Rudeus joins the effort to locate Roxy in a dangerous labyrinth, using high-powered earth and water magic against its monsters. The expedition’s dangers, including the Magic Stone Hydra, further expose the disparity between his own strength and Hilde’s. 242 254 257

Magic Research and Orsted

Seeking greater independence, Rudeus researches Gravity and Lightning Magic and develops aerial combat techniques. When Roxy falls ill, he attacks Orsted in anger and desperation, only to be defeated; their later exchange of intelligence reveals Hitogami’s efforts to prevent the Savior’s birth. 349 350 369 372 379

Sylphy Revelation and Asura Conflict

Rudeus learns that Fitz is Sylphy after she has already fled Ranoa with Ariel following Luke’s murder. Devastated by the revelation and convinced that Hitogami’s apostles are responsible, he reunites with Eris and seeks her help for the coming conflict in the Asura Kingdom. 398 401

Trivia

• Rudeus and Hilde are twins, though he treats himself as the older sibling because he was born a few minutes earlier. 5
• He once tried to pass off wearing stolen underwear on his head as “Kamen Rider” cosplay. 8 9
• Despite his magical ability, he cannot perform chantless healing magic. 13
• His adventurer nickname is “Mire,” derived from his frequent and highly effective use of the spell of the same name. 220 369