Evil Ninjas

Daredevil had "The Hand," the Teenage Mutant Ninja Turtles had "The Foot Clan," and even G.I. Joe had their "Night Creepers." Everybody loves random evil ninja attacks! So what is needed for this request are a band of evil ninjas who hire themselves out to various bad guy factions. Look into some of the above-mentioned groups to learn more about them and maybe get some inspirations.