RingMan
Ring Man has a big advantage when you battle him- the way he moves around and his attack pattern. He sends out a never-ending stream of Ring Boomerangs. He was created by Doctor Sergi Cossack. In "Bob and George," the hit comic by Dave Anez, he is the only Robot Master who has a degree of competency (Simply because he has no personality), possibly excluding Shadow Man, Elec Man, and Bomb Man.
RingMan from cartoon show
Codename: DCN-028
Weapon: Ring Boomerang
Weakness: Pharoh Shot