Shundan

Shundan (瞬断, Power Flicker) is a perfected version of invented by Raian Getsueikirite for his use only.

Description
Following the nineteen-month timeskip, Raian developed, through training under Hanzei Kurosaki, the ability to utilize Kidō in a manner that was unique to him. In Hanzei's words, Kidō is one of Raian's greatest strengths, and as such, only he would be capable of utilizing it in a way that would surpass even a Shinigami's methods. By infusing Kidō into a part of his body, he can influence the cells with his Kidō, allowing him to empower his body parts in numerous ways. Hanzei coins the term Biocellular Kidō (バイオセルラー•鬼道, Baio Serurā Kidō; literally "Biocellular Demon Way") to describe its activation.

Raian can normally influence the cells of his body in a specific region. By infusing Kidō into the cells in his legs, he can accelerate his movements and even allow himself to jump higher, much like that of a Fullbringer's Bringer Light. By doing the same to his leg while a kick is mid-air, he can cause the kick to speed up, creating a faster and stronger kick altogether. The same applies to his arms: when the cells of his arm muscles are influenced by Kidō, his punches become exceedingly stronger and faster, allowing him to easily fool an opponent at any time. In addition, he can also use Kidō on his brain cells and eyes, which makes him capable of following movements by sight that he would normally be incapable of noticing or tracking. Whenever a body part of his is influenced by Kidō, a flash of light is produced, similar to Bringer Light.

Shundan itself is a creation of Raian's own, which involves infusing every single cell in the body by Kidō at the same time. Raian considers it "the perfect Shunkō." Unlike the unstable electric appearance of the standard Shunkō, Raian's variation appears as a fiery calm aura that surrounds Raian's entire body. The speed and strength that comes from this form is nearly unrealistic, allowing Raian to contend even with a Royal Guardsmen's Bankai with minimal effort. A unique trait of this form is that because Raian's body cells are infused with Kidō energy, he can activate a full-powered Kidō from any body part without a command or incantation, such as utilizing Danku to cover his entire arm in a liquid-like form, or forming chains from any part of his body through the Sajō Sabaku spell. However, these abilities come at a price. Due to the force being exerted on each cell in Raian's body, he can not prolong usage of this form for longer than twenty seconds when he first mastered it. Although, through training, it appears that he can maintain the state for an undetermined couple of minutes. In addition, he can increase the strength, speed, and power supplied in this form by exerting more stress on the body cells via more Kidō energy infused into each cell, although the time in which he can then maintain the heighted form is severely reduced.