Su Yu

Biodata

Feature	Value
Name	Su Yu (苏宇)
Alias(es)	Li Feiyu; “Ten Thousand Hand Tang Person”
Gender	Male
Affiliation	Martial Soul Hall; Crown Prince's Residence; Heaven Dou Royal Team
Occupation/Role	Soul Master; sheriff of Swan City under the Li Feiyu identity
First Appearance	1

Power Progression

Stage / Realm / Level	Chapter	Notes
Innate Full Soul Power	1 2	Identified as an Innate Full Soul Power genius before awakening the Brass Book.
First soul ring	4	Kills and absorbs the soul ring of a Golden Lion King; gains Rule Setting.
Two-ring Soul Grand Master	40 44	His second soul ring expands punishment beyond direct harm, including exile/teleportation effects.
Level 30	63	Breaks through after fully digesting the power of his second soul ring.
Level 33	65	Absorbs the Lake Spirit Python's soul ring and gains Spirit Pierce.
Quasi-Soul Ancestor	83	Absorbs a Hundred Thousand Year Thought Worm Soul Bone and obtains two mental abilities.

Background / History

Su Yu was born in Full Moon Village as a posthumous child. His mother died in childbirth, and he survived on villagers’ charity. In return, he helped with tasks within his ability and became a lively, well-liked leader among the village children. Before awakening, he expected that, as an orphan without a notable bloodline, he might remain an ordinary person. 1

At six years old, Su Yu was taken from the village by Snake Lance Douluo on Qian Renxue’s orders. Qian Renxue, posing as Crown Prince Xue Qinghe, had learned that he possessed Innate Full Soul Power. Su Yu chose not to resist recruitment into Martial Soul Hall, recognizing that he lacked the strength to refuse. 1 2

His martial soul awakened as the Brass Book, also called the Book of Rules: a golden, thin-brass book that records and enforces rules. Qian Renxue arranged for him to reside in the imperial palace, while Emperor Xue Ye sought to bind him to the imperial family, including through a proposed engagement to Princess Xue Ke. 2 6 46

After a month of recuperation and study, Su Yu entered Sunset Forest with Qian Renxue and selected the Golden Lion King of a lion pride as his first soul-ring target. He reasoned that a pack beast’s king would be an appropriate choice. 4

Su Yu later traveled with Qian Renxue to obtain his second soul ring, but Di Tian captured him and brought him before Gu Yuena at the Lake of Life. This began his connection with the soul beast faction; Di Tian later gave him a Silver White Dragon Scale for emergency protection. 30 47

As he grew stronger, Su Yu operated in Swan City as the sheriff “Li Feiyu.” There, he used the Brass Book’s jurisdictional effects to pursue the “Invisible Enforcer” case and draw out Clear Sky Sect members. 60 63 68

Appearance

At nine years old, Su Yu was already about 1.7 meters tall due to the forced growth caused by his first two soul rings. He is described as growing into a notably handsome youth. 29 46

• Carries the Brass Book, a thin golden/brass-colored book, as his martial soul. 2 3
• Later gains wind- and lightning-attributed external spirit-bone wings. 60
• Uses the external spirit bone as part of his Li Feiyu disguise. 60

Personality

Su Yu is pragmatic, calculating, and sharply aware of the difference in power between himself and stronger figures. When first brought before Qian Renxue, he concealed his alarm and avoided asking questions he believed would not be answered. 1 2

He is highly methodical in both battle and politics. He studies soul beasts, maintains written countermeasures for different martial souls, identifies loopholes in his own rules, and continuously revises them to better protect himself. 4 43 44

Despite his strategic nature, Su Yu often speaks with teasing irreverence. He bickers with Xue Ke, provokes opponents such as Hu Liena and Yan, and frequently needles Qian Renxue even while relying on her support. 3 44 102 103

His treatment of enemies can be ruthless. He uses rule-based punishments, interrogation, and deliberate deception to extract information or deter threats, while generally retaining control over the lethality of his punishments. 44 56 70

Abilities & Skills

Brass Book

Su Yu’s martial soul is an innate god-level tool-type martial soul associated with the rules of the world. Its long-term potential includes gradually altering underlying world rules after he obtains his seventh soul ring and Martial Soul Avatar. 5 15

• All of Su Yu’s soul rings produce aspects of the same core ability: Rule Setting. 5
• Its effectiveness, duration, range, and number of active rules rise with his soul power and soul-ring count. 5
• Rules that align with public perception require little soul power; less reasonable rules cost more to establish. 5
• Su Yu can designate allies as “enforcers,” granting them partial immunity from rule violations. 5
• The Brass Book’s rules have loopholes; Su Yu mitigates them by creating more precise rules and maintaining prepared “packages” for different opponents. 43 44

Rule Setting

Su Yu’s first soul skill establishes enforceable rules within his effective range. Violators receive invisible, formless punishment, and repeated violations intensify the penalty. 5

• Initially covers a 100-meter radius. 5
• Can punish violations with invisible cutting attacks that leave non-vital but extensive wounds. 44
• Has exiled opponents from the Crown Prince’s Residence after repeated violations. 43 44
• Can punish lies through a contract-based “lie detector” application. 14 56
• Can use rules to create barriers, confuse opponents, and interrupt attacks. 103
• His usual rules exclude the “Supreme Death Penalty,” which he had used only a few times at age six. 44

Second Soul Ring Effects

After obtaining his second soul ring, Su Yu’s punishments are no longer limited to direct physical harm. 40

• Can exile targets through rule enforcement, removing them from the immediate battlefield. 40 43
• Allows Pufferfish Douluo to stop expending soul power on maintaining a protective barrier for Su Yu. 40
• Creates a delay before punishment fully activates, which fast enemies may attempt to exploit. 44

Spirit Pierce

Su Yu gained Spirit Pierce after absorbing the Lake Spirit Python’s soul ring. 65

• Acquired alongside his advance to level 33. 65

Thought Worm Soul Bone

Su Yu absorbed a Hundred Thousand Year Thought Worm Soul Bone. 83

• Blind Stupidity — one of two abilities granted by the soul bone. 83
• Thought Stagnation — a mental ability granted by the soul bone. 83

External Spirit Bone

Su Yu possesses an external spirit bone that grants wings with wind and lightning attributes. 60

• Provides a disguise component for his Li Feiyu identity. 60
• Its lightning can be used offensively; he used it to cut Hu Liena’s hair during their spar. 103

Physical Constitution

After consuming two immortal-grade herbs, Su Yu’s physical condition was greatly enhanced. 68

• Immune to ice and fire. 68
• Impervious to poisons. 68
• Uses Whale Rubber to improve his physical capacity for future soul-ring absorption. 14 15

Equipment / Items

• Brass Book — his martial soul and the medium through which he sets rules. 2 5
• Storage Soul Tool — carries notebooks containing counters to martial souls and enemy types. 44
• Silver White Dragon Scale — given by Di Tian; Su Yu can inject soul power into it to seek emergency aid. 47
• Countermeasure notebooks — records penal codes and plans for anticipated combat situations. 44

Relationships

• Qian Renxue — patron, protector, strategist, and closest long-term partner; they keep each other’s secrets and repeatedly plan around threats together. 2 14 35 46
• Xue Ke — princess whose proposed engagement to Su Yu is repeatedly raised by Emperor Xue Ye; they share a playful, argumentative friendship. 3 6 46
• Pufferfish Douluo — protector and frequent partner in Su Yu’s investigations, battles, and interrogations. 41 53 68 70
• Snake Lance Douluo — initially abducted Su Yu on Qian Renxue’s order; later escorts and supports him. 1 4 68
• Di Tian — initially captured Su Yu, then became a protector acting under Gu Yuena’s orders; entrusted him with a dragon scale. 30 47 65
• Gu Yuena — soul beast leader who investigated the Brass Book and later supported Su Yu’s growth through Di Tian. 30 47 65
• Qian Daoliu — Qian Renxue’s grandfather; recognizes Su Yu’s potential and consults him on major strategic decisions. 15 36 83
• Aornia — friend from the Full Moon family; Su Yu befriended her quickly and showed concern over her family’s treatment of her. 8 53 60
• Ning Rongrong — acquaintance and teammate; she invited Su Yu to the Great Soul Arena’s VIP box and later joined the Heaven Dou Royal Team with him. 53 88
• Bibi Dong — discusses martial-soul divinity and the Rakshasa Evil Intent with Su Yu; their interactions mix tension, debate, and mutual provocation. 47 105 106
• Dugu Bo — became curious about Su Yu’s martial soul after intercepting his party near Sunset Forest. 6
• Hu Liena, Xie Yue, and Yan — members of Martial Soul Hall’s Golden Generation whom Su Yu defeats during a spar. 102 103

Story Role / Major Arcs

Recruitment and First Soul Ring

Su Yu is identified as an Innate Full Soul Power orphan, taken to the Crown Prince’s Residence, and recruited into Martial Soul Hall. He awakens the Brass Book and obtains his first soul ring from the Golden Lion King, gaining Rule Setting. 1 2 4 5

Development of the Brass Book

With Qian Renxue’s support, Su Yu tests Rule Setting, develops contract-based lie detection, and discovers that rule punishments consume far less soul power than expected. Martial Soul Hall begins gathering Whale Rubber to strengthen his body. 5 14 15

Star Dou Forest and Soul Beast Connection

While seeking his second soul ring, Su Yu is taken by Di Tian to Gu Yuena. He later reveals knowledge of the Ice and Fire Dragon Kings’ burial ground and establishes a more cooperative relationship with Di Tian and Gu Yuena. 30 35 65

Combat Training and Rule Refinement

Su Yu tests his abilities against Li Suo and Igor, demonstrating that his rules can punish, exile, and evade stronger Soul Kings. He openly acknowledges that the Brass Book has loopholes and compensates through preparation and revised legal formulations. 42 43 44

Swan City Sheriff

Using the identity Li Feiyu, Su Yu becomes sheriff of Swan City. By carrying the Brass Book through the territory, he expands its enforcement range across the jurisdiction and uses rule-based provocations to investigate the Clear Sky Sect. 60 63 68 70

Martial Soul Hall Strategist

Su Yu advises Qian Renxue on exploiting the Clear Sky Sect’s destruction and offering the Seven Treasure Glazed Tile Sect martial-soul evolution through Aromatic Silk Beauty. He later helps Qian Daoliu prepare for future conflict by monitoring Tang San. 79 83

Golden Generation Spar

At Qian Renxue’s request, Su Yu spars with Hu Liena, Xie Yue, and Yan. He withstands Hu Liena’s charm through superior mental power, confuses Yan, blocks the group’s attacks, and decisively outmaneuvers them. 102 103

Trivia

• Su Yu recognizes the Douluo Continent from a previous life. 1
• He initially referred to his martial soul as the “Lie Detector Book” while interrogating an assassin, despite its actual name being the Brass Book. 56
• Tang San later calls him the “Ten Thousand Hand Tang Person.” 108
• Su Yu maintains at least four notebooks in his storage soul tool, though only one is openly shown to Qian Renxue. 44