Soul Reapers can only be seen by other spiritually aware beings, which excludes most humans. Additionally, they can be injured and die, like regular humans, though it takes considerably greater injuries to die than it would for regular humans.
All Soul Reapers possess a zanpakutō (斬魄刀 "soul-cutting sword"?), a weapon which reflects aspects of their soul and personality. Some zanpakutō spirits even possess similar physical traits to their wielders such as hair color and eye markings. By learning the name of the sword's spirit, and through training, Soul Reapers can unlock more powerful transformations of their zanpakutō. The first transformation, known as shikai (始解 "initial release"?), changes the sword's appearance to better facilitate its special abilities. A shikai also acts like a binding contract between a Soul Reaper and the sword and assures that no one but the owner of the weapon can use it to its fullest. The second transformation, known as bankai (卍解 "final release"?), can require ten years minimum for a Soul Reaper to master. Once achieved, the Soul Reaper can unlock the full potential of their zanpakutō, increasing their own power several times over. Though rare, it is not impossible for two people to manifest the same zanpakutō and spirit. This is considered the ultimate taboo of the Thirteen Court Guard Squads and the individuals who manifest the spirit are forced to fight to the death to determine the zanpakutō's true master, as in the plot of Bleach: The Diamond Dust Rebellion. Many Soul Reapers are able to use kidō (鬼道?, literally, "way of the demon"), a form of magic that can be performed by reciting a specific incantation. Most of the kidō spells seen in the series are used as attacks, defensive measures, or to bind others, though they can also serve more specialized needs such as healing wounds or communication over long distances. Spells are ranked on a scale from 1 to 99, indicating their complexity and overall power. Low-level spells can, however, be as effective from a skilled kidō user (e.g., Byakuya Kuchiki).
Soul Reaper operations are based out of the Soul Society, which is an afterlife realm in Bleach. Travel between the human world and the Soul Society is extremely limited and monitored, but some Soul Reapers are stationed in the human world to carry out their duties. If this Soul Reaper is an assistant captain or a captain then they will have a Gentei Reiin, or a Spirit Restriction Seal, on some area of their body. This seal will limit their spiritual powers to one-fifth of their full power and it can only be released in a state of emergency. In addition to these laws, it is a crime for a Soul Reaper to remain in the human world for longer than directed. A Soul Reaper's duties include leading wandering spirits to the Soul Society by giving a soul funeral (魂葬 (こんそう), konsō?), and to cleanse Hollows (fallen souls) of their sins. High-level Soul Reapers and similarly powerful beings are able to levitate by standing on the spiritual energy in the air.
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