In the universe of bleaching Zanpakuto are among the most powerful weapons, and although they look like katanas, mastering zanjutsu and field experience allows shinigami to attain the two evolutionary stages of blades, shikai and bankai. After discussing the bankai, let’s analyze the first form and answer the question: What is Shikai?
The relationship formed between a Shinigami and one’s zanpakuto is unique and cannot be shared. In order to reach high positions in the Gotei 13 hierarchy, every Shinigami must be able to do so Know the name of the spirit contained in the swordknowing how to contact and communicate with him, and to reach higher levels of power also knowing how to control him.
To tap into the Shikai, literally referred to as the initial releasea shinigami must perform a brief ritual consisting of uttering a cry for liberation, or even kaigo, which varies from a simple verb to a poem, as in Jushiro Ukitake, followed by the name of the spirit of Zanpakuto.
Once the whole formula is spoken The Shikai activates, transforming the blade and granting special abilities to the user. The most powerful Shinigami able to reach the Bankai cannot even say the command before the name to activate the Shikai.
The first time a god of death manages to activate the shikai, it is called kengen, or manifestation, and signifies the achievement of good control over the zanpakuto. So basically The Shikai is the first upgrade of a Zanpakuto, and its second form after the sealed version. It is also the result of the deep bond between a shinigami and the spirit of the weapon, as well as a necessary requirement for climbing the Gotei 13 hierarchical ladder.
Finally we remember that Tite Kubo could add new Bankai in the sequel to Bleach and we leave you a summary of the origins of the Hollow part of Ichigo.