Xu Yun

Biodata

Feature	Information
Name	Xu Yun (徐云)
Alias(es)	Luo Feng; Han Li; “Daily Update of Thirty Thousand”
Gender	Male
Affiliation	University of Science and Technology of China (USTC); Huadun Biotech; Cambridge University; Su Manor; Immortal Slaying Sword project team
Occupation/Role	Researcher, inventor, teacher, time-traveling Instance participant
Status	Active

Background / History

Xu Yun is a modern researcher whose Halo enables him to enter historical Instances. Before entering the Northern Song Instance, he prepares practical supplies—gold and silver fragments, a fire-hardened knife, a ceramic bottle, wig, and compressed biscuits—to avoid relying on others for survival 101.

In the Northern Song, Xu Yun awakens in Su Song’s estate and deduces the Song Dynasty and likely Yuanyou era from local clothing and toothbrush use. He becomes a contracted servant of Su Manor, aiming to fulfill Su Song’s wish before the elder dies and to keep him in Bianjing 105 106 113. He earns trust through medical treatment, inventions, teaching, and technical knowledge, including chalk, a mercury thermometer, improved iron casting, and nickel metallurgy 120 131 140 164.

During the political crisis surrounding Prince Jian, Xu Yun reveals part of his knowledge of the future to Old Su and assists Xiao Zhao after the palace coup 168 170 172. Upon the Instance’s conclusion, he receives a 22-year-old Su Song—retaining his past-life memories—as a special mission reward in the modern era 181.

Xu Yun later enters a 19th-century European Instance under the name Luo Feng. He defends a caravan from English soldiers, kills James Hope Grant in a sword duel, and uses a flashbang against enemy crossbowmen 227 228. At Cambridge, he gains the chance to take its entrance examination through Little Ox’s letter and navigates academic and social hostility toward Eastern students 236 242 270.

In another Instance set during Huaxia’s early atomic-bomb development, he uses the identity Han Li. He contributes ideas to weather Doppler radar, missile design, and other research efforts while physically injured and unable to write normally 518 533 541 559 562. His technical interventions help advance the radar project and support the Immortal Slaying Sword missile team.

Abilities & Skills

Scientific Research and Technical Problem-Solving

Xu Yun applies modern scientific knowledge across biology, chemistry, physics, medicine, metallurgy, radar, and engineering.

• Independently deduced a composite model of insect sodium channels during a thirty-minute enhancement period 61.
• Developed practical Northern Song-era innovations, including chalk and a mercury thermometer 131 140.
• Proposed nickel-enhanced iron casting capable of producing more durable tools, armor, and weapons 164.
• Helped solve a transition-metal catalysis problem by using potassium ferricyanide as a balancing liquid 207 208.
• Designed and explained radar signal-processing concepts, Doppler processing, clutter suppression, and the future potential of two-dimensional radar imaging 533 541 542.
• Proposed using shock waves and launch angles to reduce the Immortal Slaying Sword missile’s propellant consumption 562.

Historical Knowledge and Adaptability

Xu Yun quickly interprets unfamiliar environments and uses future knowledge without fully exposing his origins.

• Identified his Northern Song setting through material culture and household details 105.
• Recognized historical figures and their future significance, including Su Song, Li Qingzhao, James Hope Grant, Ge Tongyou, and Wang Yaoping 106 115 227 542 543.
• Uses carefully constructed cover identities, including Luo Feng in Europe and Han Li during the atomic-bomb Instance 236 559.
• Maintains composure when questioned about his unusual knowledge and connections 144 168.

Swordsmanship

Xu Yun studied martial arts under Wang Bing in the Northern Song and practices the Laifu Sword Art.

• Chose the Sky Pacifying Sword Art manual when Wang Bing offered him martial-arts instruction 138.
• Practiced swordsmanship for more than a year with Wang Bing as a sparring partner 227.
• Though still far below Wang Bing, was judged capable of making a name for himself in the martial world 227.
• Used his sword skills in the European Instance to defeat enemy soldiers and kill James Hope Grant 227.

Leadership and Teaching

Xu Yun often translates advanced knowledge into forms his contemporaries can use.

• Taught physics concepts to Old Su and others after demonstrating chalk’s educational value 131.
• Organized projects and planned to expand his influence through contacts in the Imperial Guards 151.
• Guided collaborators through research obstacles while respecting their respective expertise 207 208.
• Joined the Immortal Slaying Sword project as Qian Wushi’s assistant and worked directly on its theoretical calculations 559 562.

Equipment / Weapons / Items

• Fire-hardened knife 101
• Small ceramic bottle resembling quick-acting heart medicine 101
• Wig 101
• Compressed biscuits 101
• Gold and silver fragments 101
• Steel sword 242
• Flashlight 242
• Nitroglycerin 242
• Flashbang used against English crossbowmen 228
• “Little Ox Summoning” experience card, temporarily raising his cognitive ability to a world-leading level 61

Relationships

• Su Song / Old Su — Mission objective, teacher, collaborator, and later modern-era roommate. Xu Yun guides him through modern society after Su Song returns with his past-life memories 106 131 182.
• Wang Bing — Northern Song military official and martial-arts instructor; trained Xu Yun and sparred with him for over a year 138 227.
• Prince Jian / Xiao Zhao — Political ally and student with an interest in science; Xu Yun assists him during the succession crisis and coup 152 172.
• William Thomson / Old Tang — Cambridge ally and mentor figure who defends Xu Yun against discrimination and entrusts Wheat to his care 242 270.
• Wheat — Cambridge associate placed in Xu Yun’s care by Thomson; Xu Yun warns him about academic traps and political risks 242.
• Evelyn Aescu — Cambridge ally who supports Xu Yun against Harvey Clement; later bonds with him over the pressure of ancestral legacies 270 316.
• Tian Haosuo — Fellow Easterner at Cambridge. They share information and agree to support one another in Europe 276.
• Lin Zhenhua — Han Hua Group collaborator who signs a strategic cooperation agreement with Xu Yun and supports his research decisions 208 220.
• Qian Wushi — Leader of the Immortal Slaying Sword project who recruits Xu Yun as his assistant and collaborates with him on missile calculations 559 562.
• Sun Junren — Radar-project leader who values Xu Yun’s ideas on Doppler radar and two-dimensional radar imaging 541 542.
• Wang Yaoping / Old Wang — Senior expert and trusted acquaintance whose unexpectedly healthy appearance in the past deeply affects Xu Yun 473 543.

Story Role / Major Arcs

Northern Song Instance

• Enters Su Manor as a servant and seeks a way to prove his value to Su Song 105 106 113.
• Builds influence through medicine, education, metallurgy, and technical inventions 120 131 140 164.
• Becomes involved in the imperial succession crisis and supports Prince Jian’s seizure of the palace 168 170 172.
• Returns to the modern era with a reincarnated, 22-year-old Su Song as his special mission reward 181 182.

Cambridge Instance

• Defends a caravan, rescues Thomson and Will, and kills James Hope Grant 227.
• Enters Cambridge through an examination arrangement secured with Little Ox’s letter 236.
• Faces discrimination within the Apostle Society, prompting Thomson and Evelyn to withdraw in solidarity 270.
• Connects with Tian Haosuo and learns that the legacy of “Fat Fish” and the Wind Spirit Moon Shadow Sect has increased opportunities for Eastern students in Europe 276.

Atomic-Bomb Development Instance

• Arrives in the era of Huaxia’s first atomic-bomb program determined to make a major contribution 518.
• Supports weather Doppler radar development and introduces ideas about digital processing and two-dimensional radar imaging 541 542.
• Joins the Immortal Slaying Sword missile project as Qian Wushi’s assistant 559.
• Develops trajectory concepts with Qian Wushi and Yu Min despite physical limitations 562.

Modern Research

• Works with Huadun Biotech and Han Hua Group on transition-metal equipment and domestic fifth-generation Imidacloprid production 207 208 220 352.
• Tackles advanced physics problems with Zhou Shaoping and Yang Lao 454.
• Prepares for a Master’s thesis defense before a committee of prominent physicists 808 838.

Notable Quotes

“Brother Haosuo, you and I are both Easterners. Meeting in Europe is truly fate. We should support and help each other.” 276

“Hello everyone, I am Han Li, I’ll be counting on your guidance from now on.” 559

Trivia

• Xu Yun’s nickname “Daily Update of Thirty Thousand” originates from the name Wang Mazi, a distinction he privately insists on maintaining 139.
• He records completed and planned projects using Morse code and English 151.
• During the atomic-bomb Instance, he demonstrates that he can write with a pen held in his mouth 533.