Shoshidai, an organization tasked with collecting cursed weaponry, dispatches two of its agents to retrieve the legendary Demon Sword Zsoltgewinn.
An abandoned baby boy is adopted and named Gai by swordsmith Amon. He becomes an apprentice, later losing his arm in a ritual gone horribly wrong.
After acquiring the Azoth Sword, Miki is ambushed by Marcus and Miura. Amon forges a prosthetic arm out of the sword Shiryu to replace Gai's lost limb.
With his soul possessed by a demonic spear, Tatsumi transforms into a monstrous entity called a Busoma. Miki takes Marcus to Shoshidai headquarters.
The Shoshidai reawaken their most powerful Chrysalis, Seiya Ichijo. After Gai's powers partially awaken, his mind reverts to that of an infant.
Ichijo attempts to test Gai's potential as a Chrysalis but is interrupted by a member of the Gabi, a group that has long fought Busoma.
With Gai in tow, Ichijo heads to Shoshidai headquarters before stopping to meet his lover, Kei. A mysterious sword appears before gamer Midoriko.
A wealthy widow hires a search vessel to find the lost treasure of pirate Throlla, who reportedly also kept a mythical weapon known as Gallon's Hammer.
Miki and Marcus are sent on a covert mission by the Shoshidai to infiltrate and retrieve an ancient weapon of the fairy world: the legendary Halbert.
A depressed Sayaka questions Amon about Gai's motives. Meanwhile, Ichijo reveals to Gai how he came to harness the power of the Chakram.
After Gai is safely brought to Shoshidai headquarters, Ichijo is ordered by Kagami to cold sleep due to his rapidly progressing change into a Busoma.
Shoshidai's new weapons are no match against the demonic powers of Zsoltgewinn, pitting Ichijo and Gai against Miura in a fierce battle.
With the long-fought battle with Miura's Zsoltgewinn coming to a dramatic end, Gai must now fulfill a promise he made with Ichijo.
Although content with his missions for Shoshidai and relationship with his girlfriend, Marcus senses something is not right after his date with Aya.
With a Busoma running rampant outside Shoshidai headquarters, Kagami reawakens three Chrysalises from cold sleep to neutralize the hostile threat.
Himiko, leader of the Gabi, locates the Busoma responsible for her comrade Soin's death. Kagami is ordered to stand down against Marcus' Azoth.
Under the care of the Gabi, Gai dedicates himself to meditation and receives a new prosthetic arm. A bullied kid seeks help from an unlikely source.
Shin undergoes a risky procedure to rid his body of the core alma. Kuromaru takes a liking to Gai after Gai rescues him from attack.
Shoshidai sends three Chrysalises to kill Miura's Zsoltgewinn, but Kyoka begs them to use their prototype vaccine on her father to save him instead.
The true reason for the Shoshidai-sponsored hospitalization of Rie and the others is revealed. Shin and Ogata ask Kuromaru to take them to meet Gai.
Shin makes a grim discovery at the hospital where Rie resides. Meanwhile, both Yasuko and Arnys pay a visit to Issei who has left the Shoshidai.
With his resentment towards Gai intensifying, Shin resolves to devote himself to combating the Busoma as a Chrysalis.
Gai's awakening unleashes chaos into the world. Busoma Zsoltgewinn in Miura's human form appears before Amon and Kigetsu.
With the all-powerful Grimms looking on, Gai and Shin face-off in a ferocious battle, wielding their respective Shiryus against one another.