Keitaikōjō

Keitaikoujou (形態荒城, Shape Elevation) is a technique which drastically empowers all of the user's abilities.

Overview
In the hopes of sharing her power with her loved ones, Sayuri's nurturing ambition led her to develop her own Juinjutsu, which came to be known as Sayuri's Juinjutsu (小百合の呪印術, Sayuri no Juinjutsu). The seal is created through the possession of Sayuri's unique chakra, which contains a fair share of metallic particles. Once her chakra has been transferred to another person, these particles attach themselves to the iron fragmentations within the individual's blood cells. As the human body continues to circulate more blood, the metallic particles are spread throughout the body of the individual, eventually forming a seal around the person's heart. Thus, similar to the Puppet-Master Seal, requires the heart to be struck with great force in order to be removed.

Those possessing the chakra of Sayuri through their veins are said to be dear and completely loyal to Sayuri, so much so that she is, quite literally, "always in their heart". For one to activate the seal for the very first time would require their chakra reserves to be completely depleted, allowing for the effects of the seal to take over their body automatically. Afterwards, experienced users have displayed the ability to transform at will with a considerable degree of control.

When activated, the seal releases Sayuri's chakra into their body, resulting in a substantial raise in terms of strength, speed and durability. This is due to her chakra being comprised of both Uchiha and Senju lineage, granting the seal holder with both the body and will power of the Sage of Six Paths, so long as the seal is active. The seal also contains a portion of Sayuri's Senjutsu chakra, causing the skin of the user to harden considerably. What was originally believed to have been Sayuri's metal was later revealed to be a thin layer of stone that covers the users body like armor, however it cannot visibly be seen. The enhanced cells of the user are said to prevent their entire body from being turned into stone, working to balance the natural energy at all times. Additionally, the user gains an extended life force while the seal is active, allowing them to sustain wounds they otherwise would not have been able to. The seal is believed to rival the work of Orochimaru, and thus, comparable to the enhancements granted by Sage Mode.

Weaknesses
From the moment of activation, the seal runs on a set timer, dependent on how much of Sayuri's chakra the user has under their possession, with the average time limit estimated to be around 5 minutes. Once the person has run out of time, their body becomes temporarily paralyzed, negating any sort of movement. When activate, the seal exerts a tremendous amount of strain upon the heart, increasing the risk of heart failure with each use. For whatever reason, the nostrils of the user are also clogged, forcing them to keep their mouth open for the duration of the seal's activation.