Kaikyō Kotei

When circumstances deem it necessary, the Kōryū can be stopped using a method referred to as Kaikyō Kotei (界境固定, Realm Boundary Fixation). Normally, lower-echelon Shinigami enter the dimension in great numbers and using a special method, pour in their reiatsu to fixate the current. However, individuals in possession of significant quantities of reiatsu can themselves suppress the current for extended periods of time but only after the insertion of four small forked blades into various locations along the Dangai's wall and as long as the user remains connected to these items for the duration.

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The Kaikyō Kotei technique was adapted by the Hollows to expand the Kōryū and close off the Dangai Precipice World. With this action, they were able to prevent travel to and from the Soul Society, trapping them in their own world. To seal the Kōryū, one must exert a massive amount of reiatsu, and so it is said that something that contains unimaginable power lies at the center of the Dangai feeding the Kaikyō Kotei.