BLEACH: The Hōgyoku, Explained

Perhaps the most important item in the BLEACH universe for its impact on what became primary plot developments and thematic explorations, the Hōgyoku is one of the series most mysterious yet most crucial plot elements. In fact, most of BLEACH is built around series antagonist Sōsuke Aizen’s pursuit and subsequent use of the Hōgyoku to achieve his aim of transcending the boundary between Shinigami and Hollow.