The group was led by Sauvix and included dozens of elite Sea Devil warriors. Each was programmed with battle orientation which would start as soon as they were freed from suspended animation. Each was dressed in secure, samurai-style armour. They were armed with sonic discs and had a larger cutting device for cutting through doors.
Elite Group One were put in suspended animation in a sea colony. Centuries later in 2084, Icthar, the last of the Triad, woke them and used them to attack Sea Base 4 to destroy humanity. They were stopped, however, when the Fifth Doctor killed them with hexachromite gas. (TV: Warriors of the Deep)