The Common Alliance Of Shinobi or the C.A.O.S was formed during the meeting of every single leader of ninja village and before the beginning of genocidal war known as the Shinobi Struggle. The alliance of every (or least most of ninja villages) ninja villages as their purpose is to repelled and to destroyed the Gatherers. The agreements and compromisions between ninja villages and ninja villages are every ninja villages are to converted their ninja academy into 'true' military camps, change its teaching and difficulties, recruit every single body-abled to military branches, passed a similar law that stated that every females in breeding age are to produce more infants, and more reformation. The C.A.O.S have even bought their research departments to more advanced level as they allowed them