An Yu

Biodata

Feature	Details
Name	An Yu (安语)
Alias(es)	Mebius — an alias he uses within an organization 97
Species/Race	Human in reality; assumes multiple Herrscher identities in Horde Slayer stages 12 38 73 82 118
Gender	Male 12
Affiliation	Reson Studio game-planning team; later associated with Anti-Entropy's work environment 1 127
Occupation/Role	World-building planner and game developer; player of the forbidden roguelike game Horde Slayer 1 2
First Appearance	Chapter 1

Power Progression

Stage / Realm / Level	Chapter	Notes
Survivor — Level 3	1	Upgrades Gun Mimicry to Level 3, allowing him to mimic an enemy weapon after killing its user.
Survivor — Level 9	1	Reaches Level 9 with Gun Mimicry 5 and Artillery Support 3; Attack Speed reaches 3 and Skill Frequency reaches 2.
Survivor — Level 11	3	Unlocks Collective Will, allowing Honkai Beasts and Honkai Zombies to gather experience and hunt for him across the city.
Survivor — Level 14	5	Reaches Level 14 with Replica Reconstruction, Artillery Support 3, and Collective Will 4.
Herrscher of the Void — Level 6	12	Clears an exclusive scenario, kills the first survivor, and receives the special identity Herrscher. Void Realm Apostle reaches Level 5.
Herrscher of the Void — Level 15	18	Possesses Twin Familiars, Void Edict, and Elemental Shield 3; Attack Speed and Edict are both at Level 5.
Herrscher of Thunder — Level 1	38	Begins a new stage with Twin Familiars, Echo, and Lightning Control 1.
Herrscher of Thunder — Level 15	39	Unlocks Lord of Myriad Phenomena and Elemental Overflow through continued upgrades.
Herrscher of Thunder — Level 13	49	Acquires Overload, improving residual-energy efficiency; retains Twin Familiars, Echo, and Lord of Myriad Phenomena.
Herrscher of Ice — Level 1	73	Begins the ice stage with Echo (Ice) and Extreme Cold 1.
Herrscher of Ice — Level 3	75	Binds Anna as his Familiar and raises Extreme Cold to Level 3.
Herrscher of Ice — Level 11	75	Reaches Level 11 after independently investigating the icebound city and its information network.
Herrscher of Death — Level 1	82	Begins Stage Six, “Death and Life,” with Life Bloom 1 and Overload.
Chimera form / second heart	105	Reveals a second heart that improves his use of Origin Power and displays a Chimera form after modifying himself with Honkai Beast material.
Herrscher of Sentience	118	Operates under the authority of the Herrscher of Sentience while pursuing the truth behind the world and its game-like structure.

Background / History

An Yu works as a world-building planner at Reson Studio under Bronya. After becoming frustrated with Horde Slayer's sparse design and dying to a pink-haired boss at Level 9, he proposes that Reson Studio expand the existing Honkai IP into a bloody Previous Era prequel centered on the Herrschers' destruction. Bronya accepts the proposal and takes charge of the project. 1 2 5

He lives with his older sister, Elysia. As Elysia becomes increasingly distressed by recurring dreams, An Yu supports her practical needs, takes her to a mental-health evaluation, and remains patient despite frequently being exasperated by her behavior. 2 9 24

Within Horde Slayer, An Yu initially treats its inhabitants as disposable game entities and prioritizes efficient farming, upgrades, and stage clears. As the game increasingly resembles the dreams and lives of people around him, he begins investigating whether the world is a game, who its player or administrator may be, and what qualified him to enter it. 30 68 118

Appearance

An Yu had reached approximately 1.8 meters in height by high school and is described as having black hair. After fusing himself with Honkai Beasts, his appearance and aura become so altered that Himeko struggles to recognize him. 60 104

• Black-haired in his ordinary appearance. 104
• Physically strong enough to stop Durandal's punch with one hand and carry Vill-V away one-handed. 59 60
• Gains a sinister, altered coloration and presence following self-modification. 104

Personality

An Yu is analytical, competitive, and intensely mechanics-focused. He dislikes relying solely on reflexes when a fight can be solved through preparation, calculation, positioning, equipment, or superior numbers. He frequently studies opponents' habits, energy consumption, spatial patterns, and elemental interactions before exploiting their weaknesses. 39 40 48 77

His early conduct in Horde Slayer is ruthless and detached. He sees most enemies as sources of experience, treats destructive acts as gameplay, and considers loyalty or friendship exploitable weaknesses. 18 30 31

In reality, he is more patient with family and friends than his in-game behavior suggests. He is protective of Elysia, comforts Anna during crises, and can show tact around elders and professional partners. 9 75 92 He nevertheless remains highly pragmatic, often judging relationships through usefulness, risk, and whether another person can interfere with his goals. 96 98 99

Abilities & Skills

Gun Mimicry and Artillery Support

An Yu's original Survivor build centers on acquiring and reproducing weapons.

• Gun Mimicry allows him to mimic an enemy's weapon after killing them. At higher levels, everything within his sight can become his “subject.” 1
• Artillery Support manifests gun barrels around his body and evolves its shells according to the strongest weapon he understands. 1
• He prioritizes Attack Speed, reaching a 60% increase at Attack Speed 3 and 80% at Attack Speed 4. 1 12

Familiars

An Yu can create, bind, and direct companions to fight or gather resources.

• Twin Familiars grants a companion beast and increases his initial Honkai-energy quantity by 1000 hw. 11
• Collective Will enables masses of Honkai Beasts and Honkai Zombies to hunt lesser enemies and collect experience independently. 3
• He summons a Demon Dragon, later identified as Benares, as a powerful flying familiar and agent of destruction. 11 12 30
• Familiars can inherit his basic skills and traits; he binds Wendy and later Anna during separate stages. 62 75

Void Realm Authority

As the Herrscher of the Void, An Yu gains control over Imaginary Space and the boundaries between realms.

• Void Realm Apostle summons Subspace Spears and raises his affinity with Imaginary Space. 11
• He can enter Imaginary Space to evade attacks, manipulate spears, and use spatial vibrations to inflict stacking true damage. 11 12
• Void Edict lets him connect and manipulate barriers between two realms; its passive grants authority over both connected realms. 12
• His Void attacks can apply Edict stacks, increasing the precision and damage received from subsequent Void Realm attacks. 12
• Secondary Resonance allows him to anticipate and avoid attacks by analyzing enemy actions and recorded combat patterns. 30

Thunder and Electromagnetic Manipulation

As the Herrscher of Thunder, An Yu weaponizes lightning, magnetic fields, and residual energy.

• Lightning Control lets him directly manipulate lightning for offense. 38
• Echo creates a super-armored shield; when broken, it releases massive paralysis damage. Paralysis can be reduced through resistance. 38
• Elemental Overflow and its upgrade Overload improve his efficiency in using residual energy, particularly residual lightning. 39 49
• He uses magnetic fields and stored currents to create automatic evasion measures, suspend terrain, and attack from multiple directions. 40
• He can distort sound and light to loop or disable surveillance footage within his perception range. 56

Wind Manipulation

During the wind stage, An Yu develops a defensive, equipment-assisted fighting style.

• Wind Manipulation later advances into Wind Chant. 62
• Ideal Airflow forms an invisible barrier that precisely deflects attacks and prevents heat transfer through it. 64
• He combines airflow control with spatial movement and Divine Keys to fight stronger close-range opponents. 64

Ice Authority

As the Herrscher of Ice, An Yu freezes molecular movement and increases the force between molecules.

• Can freeze a city and summon Honkai Beasts during combat. 76
• Uses ice's electrical conductivity to trap Elysia, Kevin, and Kalpas. 77
• His ice constructs are difficult to break through brute force, though space-cutting attacks can sever them. 76
• His personal combat ability is assessed as comparatively weak because he cannot freely alter his living body like an inanimate object. 76

Regeneration and Chimera Physiology

An Yu eventually modifies his body with Honkai Beast material.

• Fuses with Honkai Beasts in Northern Europe, gaining new power at the cost of drastic physical and psychological changes. 104
• Possesses a second heart, resolving a compatibility issue with Honkai Beasts and allowing smoother use of Origin Power. 105
• Can rapidly regenerate severe wounds, including restoring damaged limbs within seconds. 85 86
• Reveals a Chimera form during combat against Kevin, Elysia, Himeko, and Kalpas. 105

Analysis and Information Gathering

An Yu frequently compensates for imperfect knowledge through rapid learning and observation.

• Uses Mei's calculations and his own testing to build combat functions around electromagnetic and spatial phenomena. 39 40
• Studies enemy behavior, weapon mechanics, and game-system rules to turn instantaneous reactions into preplanned actions. 48
• Can rapidly absorb information from databases and conduct broad online research. 75
• Reads and processes a passerby's accumulated memories to investigate Elysia's reforms. 115

Equipment / Weapons / Items

• Key of the Void — spatial Divine Key used for mobility, attacks, and battlefield control. 56 64
• Seven Thunders of Retribution — Divine Key used for extreme single-target breakthroughs and the First Rated Power technique. 64
• Subspace Spears — Void Realm weapons summoned through his Herrscher authority. 11 18
• Violin — an instrument he can play skillfully, though he avoids doing so when it could expose his identity or habits. 96 102 109

Relationships

• Elysia — his older sister in reality. An Yu supports her through her mental-health struggles, while their dream-world encounters repeatedly place them on opposing sides. Elysia also refers to a past marriage between them, though their relationship remains emotionally complicated. 9 48 70 83
• Bronya — his boss at Reson Studio and professional partner. An Yu proposes the Honkai prequel project, while Bronya handles its final direction and production decisions. 1 2 5
• Anna — his Familiar during the ice stage and later his girlfriend. An Yu offers to trade places with her, reassures her during their flight from Fire Moth, and she openly expresses love for him. 75 76 133
• Himeko — an associate whose attachment to An Yu becomes increasingly strained by his pragmatism and self-modification. She joins Poison Cocoon but continues trying to understand or bring him back. 96 99 104 105
• Wendy — An Yu's university classmate and chosen Familiar during the wind stage. After her death, he buries her beside Elysia's grave and marks the site “Wendy’s Grave.” 62 65
• Kevin — a recurring opponent in several game stages. An Yu repeatedly defeats or outmaneuvers him through spatial, electromagnetic, and elemental tactics. 30 40 77 85
• Mobius — researcher and occasional confidante. They discuss human evolution and superhuman experimentation, but An Yu later deceives her and steals genetic blueprints. 98 102 104
• Vill-V — a researcher interested in An Yu's unusual genetic fragment. He initially rejects her proposal, then later agrees to cooperate in pursuing Divine Key creation and the Herrscher Core. 59 118
• Durandal — a straightforward acquaintance and sparring partner whom An Yu defeats with overwhelming physical strength. She later attempts to help him enter Schicksal. 59 60 127
• Kiana — a former college senior whom An Yu initially remembers as an “ice princess.” Their relationship is complicated by Kiana's visible attachment and his connections with Anna and Elysia. 15 92

Story Role / Major Arcs

Reson Studio and the Forbidden Game

An Yu begins as a planner struggling under Bronya's expectations while secretly playing Horde Slayer. After dying to its pink-haired boss, he pushes Bronya to develop a Previous Era Honkai prequel built around Herrscher violence, tragedy, and historical escalation. 1 2 5

Herrscher of the Void

An Yu develops a familiar-based Survivor build, gains the Herrscher identity after clearing an exclusive scenario, and becomes the Herrscher of the Void. He destroys cities, kills Sakura in front of Elysia, defeats Kevin, and eventually kills Elysia after exploiting her concern for others. 3 12 18 30 31

Thunder and Wind Stages

As the Herrscher of Thunder, An Yu devastates Nagazora and fights Kevin and Elysia using lightning, magnetic fields, and calculated spatial movement. In the subsequent wind stage, he binds Wendy as his Familiar, uses Divine Keys against Kalpas, and later buries Wendy after her death. 38 40 62 64 65

Ice and Death Stages

As the Herrscher of Ice, An Yu protects Anna, offers himself in exchange for her release, and later accepts responsibility for his crimes rather than fleeing with her. During the Death stage, he accompanies Elysia while she struggles to understand her destructive powers and seeks Elysian Realm. 75 76 77 82

Self-Modification and the Search for Truth

An Yu becomes increasingly suspicious of the dream world's structure. He infiltrates Fire Moth, steals genetic blueprints, fuses himself with Honkai Beasts, develops a Chimera form, and seeks the truth behind Elysia, Honkai, and the apparent game system. 102 104 105 118

Cooperation with Vill-V

As the Herrscher of Sentience, An Yu approaches Vill-V's personalities to discuss the origin of Honkai and Elysia's role. He proposes retrieving the Herrscher Core or participating in the creation of a Divine Key, while considering the possibility of locating and killing the world's player and administrator. 118

Notable Quotes

“I'm a god when I play a single-player game!” 30

“People like you, who value loyalty and friendship, really are easy to bully...” 30

“If you're still afraid, call my name. I'll definitely answer you then. I'm here.” 75

“I want to retrieve the Herrscher Core.” 118

Trivia

• An Yu was a college football star and later dominates every event at Anti-Entropy's anniversary celebration. 91
• He is an accomplished violin player, though he deliberately avoids playing openly when it could reveal traces of his identity. 96 102 109
• He once considered pursuing civil service work and marrying into a wealthy family if his business career failed. 35
• He prefers games that let him rapidly “mow down” enemies and is consistently irritated by Horde Slayer's story scenes, dialogue, and perceived design flaws. 1 3 62