Yayax Squad was an elite clone commando unit, and was part of the Grand Army of the Republic during the Clone Wars. They were one of the squads trained by Rav Bralor on Kamino. Members of Yayax Squad, like those of Omega Squad, wore matching Katarn armor, a gray-and-brown dazzle-pattern which gave them a degree of camouflage in an urban environment. This gave them an advantage during the Battle of Coruscant.
During the Battle of Coruscant they assisted Omega Squad and ARC Trooper Lieutenant Aven in defending the HNE Headquarters building from Separatist attack. They succeeded in protecting the building from droid attacks. They then assisted the CSF in maintaining domestic security on the capital. After Order 66 was enacted and Palpatine established the Galactic Empire, Yayax Squad deserted and joined Kal Skirata on Mandalore. They were taken to Mandalore by Nyreen "Ny" Vollen and A'den when she brought the body of Etain Tur-Mukan to Kal.