Royal Guard

The, also known as the Zero Division (Squad Zero in English), is made up of former Captains of the Gotei 13 who have been promoted to this level. Only captains of the Gotei 13 know of their existence, excluding former Lieutenant of the 8th Division, Vizard Lisa Yadomaru, and Rukia (from episode 14 mentioning them). They are said to have considerable power and tactical knowledge. The Royal Guard are expert Shinigami that were promoted for the sole purpose of protecting the King (Spirit King), the true ruler and figurehead of Soul Society.

Membersto
All members of the Royal Guard are former Captains of the Gotei 13. Only one has ever been mentioned in the series: who was the Captain of the 12th Division.