Pearl Prison

The Pearl Prison was a white pearl used by Oseuth to imprison Iuchi Karasu and the infamous Kuni Yori.

Binding Kuni Yori
In 1133 during the march to Volturnum Iuchi Karasu confronted Kuni Yori. Only by sacrificing his life in a magical ritual was he able to help contain Yori, sealing both their souls in a mystical Naga Pearl. With the aid of Oseuth, the reincarnated Warrior of the Pale Eye, Karasu drew both himself and Yori into the magical pearl, stopping Yori's plans.

Gisei Toshi
The Pearl eventually found its way into the hands of the Phoenix, who stored it in the temples of Gisei Toshi.

Released
Iuchiban's rampage through Gisei Toshi in 1165 allowed Yajinden, Iuchiban's lieutenant, to steal the pearl. Yajiden bargained with Yori and freed him.