Welt

Bioddata

Power Progression

Background / History

Welt inherited the Herrscher of Reason’s core, title, and duty from the dying Joyce. Initially frightened and uncertain of what to do with such power, he was taught by Joyce’s companions and ultimately committed himself to protecting humanity, repeatedly risking or sacrificing his life against the Honkai. 218 324

Before joining the Astral Express, Welt served as Anti-Entropy’s Alliance Leader. The Void Archive, the First Divine Key of the Previous Civilization, brought him through a Star Gate into the Honkai: Star Rail world; Welt remains wary of it and initially suspects it when an unknown sphere approaches the Express. 5

His childhood name was Joachim. By the time of the Luofu expedition, he had passed the Herrscher of Reason core to Bronya and retained only part of its authority, explaining the limitations of his power before Theresa supplied a new core. 135 220 324

Pam remembers Welt’s arrival as an important turning point for the Astral Express: his dependability made Himeko’s subsequent trailblazing considerably smoother. Before Theresa’s arrival, Welt also retrieved the drifting ice containing March 7th, bringing it aboard the train at Pam’s request. 691

After Welt disappeared through the Star Gate, Tesla and Einstein searched Saint Fontaine with Anti-Entropy mechs. They recovered a phone at the place where his presence was last detected, and Tesla eventually devoted herself to spatial-travel research in the hope of finding him. 705

Appearance

Following his transformation into the Herrscher of Truth, Welt appears visibly younger while retaining white streaks in his hair. He is usually seen with glasses, a cane-like Star of Eden, and his reconstructed sweater, jacket, trousers, and scarf. 221 243

• His Herrscher eyes manifest as gear-shaped patterns:
  • Red when angered or in Yang Chaoyue’s battle stance. 218 430
  • Blue when using his authority in a good mood. 433
• He can restore damaged clothing through his reconstruction ability. 243
• Theresa used a bow supplied by Aha to temporarily transform him into an adult Bronya-like female form, complete with silver-grey hair and a pink-and-blue bow. The form wore elegant, asymmetrical armor resembling formal attire, including a wing-like shoulder cape and silver-blue ribbons. 224
• During the staged Journey of the Fire, he wore a mask that made him appear much younger and more handsome for his role as the First Herrscher. 469
• His later magical-girl form resembles the petite Zhong Li; after exhausting its power, he returns to his tall male appearance. 721

Personality

Welt usually presents himself as mature, composed, polite, and dependable, especially around younger members of the Astral Express. He prioritizes the safety of the crew, warns others against reckless uses of dangerous power, and chooses to undergo his own metamorphosis far from the Express and the Luofu to prevent collateral damage. 5 86 216

He is a cautious planner who readily takes responsibility in negotiations and crises. He investigates threats, assesses political risks, and often acts as the group’s spokesperson when dealing with authorities such as Yukong and Jing Yuan. 93 96 154

Theresa’s familiarity with his past regularly breaks his carefully maintained image. Her teasing exposes his enthusiasm for robots, magical-girl media, manga, and other hobbies that he would rather keep private. 58 154

His composure is particularly vulnerable to reminders of Otto. When Theresa’s prank makes an Otto-like traveling merchant deliver a deliberately provocative message, Welt attacks in fury before accepting that the encounter was a misunderstanding. 171 172

Despite his embarrassment over transformations and theatrical performances, Welt places others’ safety first. In his magical-girl form, he abandons concern for his reputation long enough to intercept a dangerous Astral Express projection, only forfeiting after the immediate danger has passed and he returns to normal. 721

Welt remains firmly attached to his identity as a man and to Tesla. He explicitly rejects the suggestion that he enjoyed permanently becoming Bronya, and later reassures Tesla that he loves only her when she notices the many women accompanying the Express. 243 705

Abilities & Skills

Herrscher of Truth Authority

As the Herrscher of Truth, Welt wields Imaginary energy and can materialize complex technological constructs at extraordinary scale. 221

• Constructs vast cosmic fleets and Star Destroyer-style warships. 221 222
• Rebuilds damaged or destroyed constructs after battle. 223
• Restores his own damaged clothing through reconstruction. 243
• Materializes robot armies, quantum barriers, microwave radiation cannons, and other heavy weapons. 244
• Can replicate and reconstruct an object before understanding it, reversing the previous restriction associated with his reconstruction ability. 243
• Repairs the Kitten Cake creation device and reconstructs a strand of his own hair for use in it. 245
• Uses his construction abilities for noncombat projects, including preparations for the new Golden Courtyard and the creation of Fire Moth soldiers and bases within a dream bubble. However, he protests that the Flame-Chasers’ increasingly elaborate Golden Courtyard blueprint exceeds his abilities. 433 469
• His post-ascension strength is assessed as comparable to that of an ordinary Emanator, and his completed transformation is later described as sufficient to destroy planets effortlessly. 222 765

The dual-core Reason-and-Void powers shown during his metamorphosis belong to an Inner Demon illusion, not a permanent acquisition. In that vision, he absorbs Sirin’s core, teleports, and creates spatial Quasi-Black Holes without Star of Eden; he ultimately recognizes the experience as a manifestation of his unresolved obsessions. 219 220

Gravity Manipulation

Welt channels the Ninth Divine Key, Star of Eden, to generate gravity fields capable of crushing enemies and controlling a battlefield. 218 219

• Crushes Honkai Beasts with a gravity field in the Siberian conflict sequence shown during his metamorphosis trial. The confrontation develops into an explicitly identified Inner Demon illusion. 218 219
• Uses Star of Eden as both a cane and a combat focus. 5 244
• Can fly and make high-speed aerial descents while carrying Star of Eden. 5 59
• Uses gravity offensively when enraged, tearing large gashes into the ground during the misunderstanding involving Ruan Mei. 171
• Can generate a black-and-gold protective membrane around nearby companions to reduce the effects of Theresa’s Divine Blessing Barrier. 11 12

Quasi-Black Hole

Welt can deploy a Quasi-Black Hole through Star of Eden’s Zero Rated Power to draw in and destroy large targets. 244

• Eliminated masses of True Stingers and defeated the Pharaoh Queen Scarab Skalacabaz with a full-release Quasi-Black Hole. 244
• Used the ability against the Abundance Xuanlu during the defense of the Forge of Creation. 136
• The technique is not a true black hole and can cause severe collateral damage or injury to Welt without protective support. 244
• Theresa’s Binding Barrier and Immortality Shield allow him to use the technique at full power without destroying the surrounding area. 244
• Can compress the technique into a miniature form to restrain a large enemy while reducing the risk to its surroundings, as demonstrated against Skalacabaz. 243
• Groups enemies for allies’ attacks. At Tide of Dreams, he pours his Path power into Star of Eden to maintain the Quasi-Black Hole beyond its usual brief duration, visibly straining himself because of its enormous energy consumption. 417
• Can use a Black Hole projection to swallow a dangerous Astral Express projection and close it before the latter explodes. 721
• His later full-power release against Romantic Tomb is described as having half the might of a real black hole. Sustaining this output beyond Star of Eden’s limits causes tiny cracks to form in the cane. 731
• Can deliberately reduce its destructive effect while preserving its restraining function. Against Gustot, he holds the dragon in place and leaves its head intact for Kukulkan rather than attempting to destroy it himself. 936

The ability is not effective against every higher-order power. His attempt to destroy a Holy Grail summoning circle evaporates on contact, while Romantic Tomb resists his full-power attack through Corruption and Destruction before immobilizing him with near-absolute-zero temperatures. 701 731

Tactical Command

Welt combines combat ability with measured leadership and battlefield planning.

• Leads negotiations with the Xianzhou Alliance and prepares the group for hostile scenarios. 93
• Warns Theresa to use Wisdom Assimilation carefully rather than treating control over others casually. 86
• Commands robotic forces and coordinates heavy weapons against large-scale threats. 244
• Shares intelligence on the Medicine Master’s Legacy and its connection to Jianmu, Yaoshi, and Mara-struck Soldiers. 154
• Secures the Express crew’s right to observe Kafka’s interrogation after Fu Xuan takes custody of her. 110
• Reassures the Knights of Favonius and Barbatos when the group arrives in Mondstadt, helping establish a peaceful reception. 761
• Coordinates quickly with Himeko in battle, understanding her unspoken request to restrain Gustot so that the others can prepare their attacks. 936

Other Traits and Skills

• Herrscher longevity — Welt states that Herrschers are not bound by ordinary lifespan limits, reassuring Tesla that he would not simply grow old before seeing her again. 705
• Comic creation — Draws Houm comics, including spending a quiet night aboard the Express working on them. 58 379
• Performance — Plays a deliberately theatrical First Herrscher during the staged Journey of the Fire, insisting that the resulting exaggerated behavior is part of his acting. 469
• Magical-girl empowerment — The Super Dimensional Concerto grants a temporary transformed state whose power grows with the user’s embarrassment. Welt can still invoke Star of Eden through the wand used in this form, but the exertion can leave him unable to maintain the transformation. 721

Equipment / Weapons / Items

• Star of Eden — The Ninth Divine Key, carried in a cane-like form and used to create gravity fields and Quasi-Black Holes. 5 218 244
  • During the early Luofu expedition, Welt describes his cane as a self-created version weaker than Star of Eden itself, though still sufficient to control the monsters confronting the group. 89
  • Later, driving the cane beyond its limits against Romantic Tomb causes tiny cracks to appear. 731
• Alahato — Welt’s beloved mecha, which he pilots and can transform into a small warship equipped with a Star Destroyer Cannon. 134 223
• Cosmic fleet constructs — Imaginary-energy-created warships and combat vessels. 221 222
• Robot army and heavy armaments — Materialized combat robots, barriers, radiation cannons, and other battlefield equipment. 244
• Houm comics — Original comic manuscripts he draws; Theresa’s interest in them once gives Welt leverage during their banter. He also uses his replication ability to produce merchandise. 58 105 379
• Adjustable-prescription glasses — Receives glasses whose prescription can be freely adjusted before leaving Jarilo-VI. 71
• Aha’s pink-and-blue bow — The wager penalty that transforms him into an adult Bronya-like woman. The bow eventually cracks under the strain, causing him to revert in public. 224 697
• Communication phone — Places the phone he uses to communicate with Tesla in a Holy Grail summoning circle as a catalyst, successfully bringing Tesla and Einstein to him. 705
• Super Dimensional Concerto — Associated with his temporary magical-girl empowerment; its unusual effect increases his power in proportion to his embarrassment. 721

Relationships

• Theresa Apocalypse — Old acquaintance from Welt’s homeland. He rescues her when she arrives adrift near the Astral Express, remains protective of her power use, and later accepts her help with his ascension; she frequently teases him. 5 86 216 243
  • Her assistance also makes Joyce’s resurrection possible, although she requires Welt, Otto, and Kevin to agree to a concert performance in return. 327
• Tesla — Someone Welt deeply cares for. Their reunion is emotional, and Welt’s commitment to her remains central even during Aha’s transformation prank. 243 705
  • Tesla searches for him after his disappearance and researches spatial travel to reach him. When reunited, Welt embraces her, calls her “darling,” and explicitly declares that he loves only her. 705
• Einstein — One of Joyce’s companions who helped raise and educate Welt after he inherited the Herrscher core. She reunites with Joyce alongside him and is later summoned together with Tesla during the Holy Grail War. 337 705
• Joyce — Welt’s predecessor and benefactor, who entrusted him with the Herrscher of Reason core, his name, and his mission. 218 324
  • Welt agrees to Theresa’s concert condition for Joyce’s resurrection and later tells the revived Joyce that he succeeded in fulfilling his responsibility. 327 337
• Himeko — Fellow Astral Express crew member and navigator. Welt trusts her competence but remains concerned for her safety during dangerous operations. 5 85
  • Pam credits Welt’s arrival with making their early trailblazing journey smoother. They later demonstrate close battlefield coordination against Gustot. 691 936
• March 7th — A younger companion who calls him “Uncle Yang.” Welt acts as a mentor and dependable senior figure to her. 59 154
  • He originally retrieves the block of ice containing her from outside the Express. 691
• Bronya — His successor as the third Herrscher of Reason and the recipient of his former core. Joyce’s surviving consciousness within that core later provides the basis for his resurrection. 135 324 327
• Otto Apocalypse — Long-standing adversary whose provocations exploit Welt’s anger and desire for revenge. 219 259
  • Despite their hostility, Welt accepts Otto’s proposal to cooperate in securing Joyce’s resurrection. During the Holy Grail War, he unsuccessfully tries to prevent Theresa from summoning Otto. 327 701
• Master Gongshu — A fellow enthusiast of giant machines; the two enthusiastically discuss Alahato and plans for a giant Xianzhou automaton. 134
• Svarog — His teammate in the Mechanical Hot-Blooded Team during an Etherium Spirit advancement match. Their giant robotic spirits defeat Seele and Bronya’s team. 532
• Aha — A recurring source of humiliation through the transformation bow and subsequent public reversion. Welt angrily threatens Aha with a miniature Quasi-Black Hole but refrains from attacking because of the danger to the Space Station and the futility of attacking an Aeon. 224 242 243

Story Role / Major Arcs

Theresa’s Arrival

While returning to the space station aboard the Astral Express, Welt identifies Theresa inside a translucent sphere drifting through space. He leaves the train through an open door, retrieves the sphere with Star of Eden, and confirms Theresa’s identity by having her unfold the Oath of Judah. 5 6

His initial caution includes checking whether she could be Void Archive in disguise. Once convinced, he apologizes; Himeko nevertheless makes him drink a cup of her exceptionally concentrated coffee for upsetting Theresa. 6

During the Doomsday Beast attack, Welt organizes the others around him and raises a black-and-gold barrier to protect them from the effects of Theresa’s Divine Blessing Barrier while she confronts the beast. 11 12

Belobog and the Xianzhou Luofu

Welt answers Theresa’s call for help at Everwinter Field after hearing that Belobog’s Creation Engine is involved. He assists Bronya, Seele, and Gepard against the Stellaron crisis and later becomes a key planner during the Luofu operation. 58 59 93

Against the Stellaron-influenced Cocolia, he attempts to use a Quasi-Black Hole. When the target evades and the attack threatens his allies, he immediately cancels it and switches to high-energy rays. 60

On the Luofu, he assesses Tingyun’s suspicious behavior, leads preparations for negotiations with Yukong, considers the consequences of revealing Theresa’s abilities to Jing Yuan, and investigates the spread of the Medicine Master’s Legacy. 93 96 154

He secures permission for the Express crew to observe Kafka’s interrogation, and later uses a Quasi-Black Hole against the Medicine Master’s Legacy after losing patience with Dan Shu’s insults. 110 163

Theresa and Dan Heng’s prank provokes him into mistaking the traveling merchant Ruan Mei for Otto. Welt’s furious attack brings Jingliu out of the merchant’s coffin, and Theresa blocks her frost blade before the group clears up the misunderstanding and resumes its journey toward the Scales Embrace Realm. 171 172

Ascension to Herrscher of Truth

Theresa gives Welt a Herrscher core so that he can complete his advancement. Concerned that the process could endanger the Astral Express or the Luofu, Welt chooses to ascend in deep space within Theresa’s Binding Barrier. 216 217

During the metamorphosis, he relives Joyce’s death and confronts an inner vision in which power, grief, and resentment corrupt him. After accepting Joyce’s legacy without losing himself to those impulses, he emerges as the Herrscher of Truth. 218 219 220 221

Theresa transports him to an uninhabited asteroid belt roughly two light-years from the Express and directs the energy within her barrier into his cocoon. Inside the trial, Welt eventually recognizes the child calling himself Joachim as a Herrscher personality born from his own obsession, rather than accepting the illusion’s offer of endless satisfying dreams. 217 218 220

Battles After Ascension

Welt tests his new power against Theresa’s angel legions, constructing a fleet and piloting Alahato. Although he fights strategically, Theresa’s Holy Dragon of Light destroys his fleet and forces him to honor their wager by wearing a pink-and-blue bow. 222 223

The bow transforms him into an adult Bronya-like woman. To conceal the embarrassment aboard the Express, he introduces himself as Bronya, a Galaxy Ranger codenamed Secondary Silverwing, and receives a room in the restored section of the train. His identity is exposed when the transformation ends unexpectedly and his male body tears through the clothing. 224 242 243

He later deploys an army of robots and a full-release Quasi-Black Hole against the Pharaoh Queen Scarab Skalacabaz. Theresa contains the resulting explosion and heals Welt’s injuries, enabling the pair to secure the Herta Space Station’s Containment Zone. 244

Afterward, he repairs the Kitten Cake creation device damaged by Theresa’s attempt to use her hair in it, then successfully creates a white-and-grey Kitten Cake using a reconstructed strand of his own hair. 245

Joyce’s Resurrection

Otto recruits Welt to cooperate with Theresa by offering the possibility of resurrecting Joyce. Welt arrives at St. Freya with Einstein, Tesla, and Coralie, where Theresa confirms that Joyce’s consciousness remains within Bronya’s Herrscher core. In exchange for the resurrection, Welt, Otto, and Kevin agree to sing “Congratulations on Getting Rich” together. 327

When Joyce awakens, Welt and Einstein explain the intervening decades, including how Welt inherited the core and became Anti-Entropy’s Alliance Leader. Welt tells his restored predecessor, “Mr. Joyce, I did it.” 337

Penacony and the Dream Worlds

In Tide of Dreams, Welt explores with Stelle and Liu Ying, although he cannot see Clock Boy when the latter appears to Stelle. Misha introduces them to the Ideation Void and takes them to Kemei, who warns that the sweet dream will consume the lower dream within ten system hours. 406

During the confrontation with the Stellaron and its monsters, Welt maintains a Quasi-Black Hole to group enemies for the other fighters. Sustaining it requires a continuous infusion of Path power and visibly strains him. 417

He volunteers to help construct the Flame-Chasers’ new Golden Courtyard in the Meme Settlement, but the residents’ additions—including amusement-park features and an artificial lake—leave him protesting the complexity of the blueprint. Later, he warns Stelle against naming their newly acquired ship the Never-Crash before the group settles on Trailblazer’s Tail. 433 443

During the staged Journey of the Fire, Welt plays the First Herrscher as a youthful, theatrical boy rather than allowing Theresa to transform him into a female character. He also constructs Fire Moth soldiers and bases inside the dream bubble. 469

In an Etherium Spirit advancement match, he partners with Svarog as the Mechanical Hot-Blooded Team. Their Alahato and giant Svarog spirits overcome Seele and Bronya’s Illusory Sea Dream Butterfly Team. 532

Welt and Himeko later choose to leave the initial Amphoreus expedition to the younger companions rather than joining the exploration team themselves. 547

Reunion with Tesla

During the Holy Grail War events, Welt uses a phone to summon Tesla and Einstein from another dimension. His reunion with Tesla confirms the longing and affection he has carried for her. 705

Before his own summoning, he recognizes Theresa’s intention to summon Otto and hurls a Quasi-Black Hole at the circle in an attempt to stop her. The attack evaporates, and Otto appears with Void Archive despite his intervention. 701

For his own catalyst, Welt chooses the phone he used to communicate with Tesla, watching the circle with intense anxiety and hope. Tesla and Einstein arrive from a spatial-transmission experiment, and Tesla tearfully embraces him. She subsequently identifies their surroundings as a world inside a Memory Bubble associated with the Holy Grail War. 705

During a later match, Welt fights in a magical-girl form empowered by the Super Dimensional Concerto. He uses a Black Hole projection to contain an explosive Astral Express projection, but exhaustion forces him back into his male form. Overwhelmed by embarrassment, he immediately forfeits while Otto teases him about his childhood enthusiasm for Teruriri. 721

When Romantic Tomb confronts the group, Welt unleashes Star of Eden at full power, restraining the enemy with an expanding Quasi-Black Hole until it counters with Corruption and Destruction. Romantic Tomb then lowers the surrounding temperature to near absolute zero and freezes him, prompting his companions to intervene. 731

Teyvat Expedition

Upon the group’s arrival in Mondstadt, Welt reassures the wary Knights of Favonius and Barbatos. Jean and Lisa subsequently offer hospitality at the Goethe Grand Hotel. 761

In Fontaine, he intervenes during the confrontation with Neuvillette, drawing the Hydro Dragon Sovereign’s enormous body into a suddenly manifested Black Hole. 876

Against Gustot, Welt recognizes Himeko’s signal and releases a deliberately restrained Quasi-Black Hole, pinning the dragon while preserving its head for Kukulkan. His control gives the others time to combine their attacks: Himeko’s satellite cannon and the Astral Express projection strike Gustot, Lumine crystallizes its body, Mavuika severs its head, and Kukulkan destroys the Abyss Power within its skull. Theresa then annihilates the remaining Abyss will, completing the group’s victory. 936

Notable Quotes

“Theresa, stop teasing me. I have successfully molted, transforming from the Herrscher of Reason into the Herrscher of Truth.” 221

“Damn bugs! Witness the power of a black hole!” 244

“Mr. Joyce, I did it.” 337

“I haven't found a way back yet. How could I grow old so easily before seeing you again?” 705

“Submit or be destroyed. You have no other choice!” 936

Trivia

• Welt is notably enthusiastic about giant robots, particularly Belobog’s Creation Engine and his own Alahato. 58 134
• Theresa claims that Welt secretly wore a magical-girl outfit as a child; Welt strongly denies it. Otto later recalls that Tesla bought the young Welt a dress matching Teruriri’s outfit, supporting the childhood story despite his earlier denial. 58 721
• He once drew and manufactured Houm comic merchandise to help subsidize Anti-Entropy, using his replication ability to produce goods at exceptional speed. 105 131
• Aha’s prank temporarily transformed him into an adult Bronya-like form; the disguise was later exposed when his clothes tore as he returned to normal. 224 242
• He later insists that the crew keep the transformation incident secret. His recollection reveals that the bow cracked under the strain, triggering his sudden reversion. 697
• Theresa’s Elysia transformation leaves him visibly flustered; he eventually follows Dan Heng’s example by closing his eyes rather than continuing to look at her. 78 79
• He initially insists that his exaggerated First Herrscher performance is purely dedicated acting, although the narration describes him as taking the opportunity to indulge his theatrical side. 469
• His later magical-girl transformation makes embarrassment a literal source of increased combat power, turning one of his recurring personal vulnerabilities into an advantage. 721