Greatsword of the North

The Greatsword of the North is the world treasure formed from the northern Heavenspan landmass and wielded by Bai Xiaochun. It combines a celestial-grade sword with an inhabited internal world: the Frigid Matriarch appears within it, captured beings can be bound there, and entire populations can shelter inside. Its power greatly increases Bai's battle strength, but the weapon can exhaust or injure him and remains vulnerable to suppression by archaean natural law. (Chapters 1028, 1043–1052, 1118, 1140–1156)

History

The northern land becomes a sword

During the collapse of the Heavenspan Realm, the northern landmass rises, sheds its earth and stone, and reveals an immense blue sword. Surviving inhabitants vanish into the treasure's interior, while the face of the Frigid Matriarch becomes visible on its surface. The sword then shrinks and flies to Bai Xiaochun, who catches it and immediately uses it against Daoist Heavenspan. Its true-celestial fluctuations destroy his vortex and maim him, although the collision also leaves Bai grievously injured and nearly unconscious. Daoist Heavenspan attributes the completed forging to his foremost apprentice, but the source does not provide a fuller manufacturing history. (Chapter 1028)

In the Eternal Immortal Domains, Bai learns that the sword has no recognized true master and can be used without the restrictions he expected. He later says that he has refined it, but the procedure is not described. As his cultivation rises, his control improves enough for him to communicate with the Frigid Matriarch inside and manage the people housed in its internal world. (Chapters 1052, 1103, and 1118)

Weapon, prison, and shield

The Greatsword repeatedly serves as Bai's strongest direct weapon. A frontal slash initially fails to penetrate the lizard bone galleon's flesh-and-blood defense, but after Bai restrains the ship and separates Ghostmother from its support, the sword helps him sever her arm. It also contains an enslavement seal used to bind a captured ghost face; the seal prevents that quasi-archaean spirit from resisting when Bai summons and returns it. (Chapters 1043–1048 and 1131–1132)

Against the Murknine County creature, the sword cuts deeply into its egg sac and later changes into a defensive form to withstand the creature's release. It holds back an attack beyond the Celestial Realm for a prolonged moment, though both sword and wielder tremble under the pressure. In later celestial battles it can expand to enormous size and lets Bai strike above his unaided cultivation level. Even so, it cannot make him equal to an archaean, overcome four celestials at once, or ignore an archaean emperor's control of local natural law. (Chapters 1138–1156 and 1177)

Refuge, entrusted custody, and recovery

The internal world becomes an emergency refuge for Heavenspan cultivators. Bai uses it to evacuate the population of Mistysea Prefecture, approaching the space's practical capacity. When he later chooses to confront the Vile-Prince, he draws tens of thousands of people into the sword and sends it away rather than expose them to his possible death. He asks Ghostmother—then commonly addressed in the narrative by the name of her host, Gongsun Wan'er—to deliver the sword and its passengers to the Grand Heavenmaster. (Chapters 1148 and 1189)

Ghostmother fulfills that request. The Grand Heavenmaster prepares the refuge, and Ghostmother keeps the sword with her while hiding from the Vile-Emperor Dynasty; neither act is described as a permanent transfer of ownership. Years later, Bai senses the sword in the Eternal Sea. It responds to their connection, flies into his hand, and yields the hundreds of thousands of people sheltered inside to populate his new domain. The last related notice says Ghostmother senses that someone has taken it, while the weapon itself remains with Bai. (Chapters 1195, 1209, and 1211)

Abilities and properties

• World-treasure offense: The sword projects immense blue sword light and amplifies Bai's cultivation into true-celestial or higher combat output. Its effect scales with his own power, but heavy use can drain, injure, or incapacitate him. (Chapters 1028, 1043–1048, and 1142–1156)

• Internal world: Living beings can enter and remain inside, allowing the weapon to shelter or transport populations. Its exact dimensions are not given, and Bai treats it as nearing capacity during a large evacuation. (Chapters 1028, 1118, 1148, 1189–1209)

• Resident communication and confinement: The Frigid Matriarch remains accessible within the sword, while an enslavement seal can restrain the captured primary ghost face. The source does not establish that every resident is enslaved or that the sword automatically controls anyone placed inside. (Chapters 1045, 1118, and 1131–1132)

• Variable size and defensive form: The sword can grow to thousands of meters and can be used as a broad defensive barrier. It can hold back attacks beyond ordinary celestial power, but it is not indestructible or sufficient to defeat such force outright. (Chapters 1138–1145)

• Limits on mastery: Bai states that the sword has no true master. Refinement and higher cultivation improve his control, yet the Vile-Emperor's natural law can pull it away from him, and even a spirit's enhancement does not make it adequate against an archaean. (Chapters 1052, 1103, 1150, and 1177)

Ownership and custody