Mega Man 4

Mega Man 4 takes place in the year 20XX (the 21st century). One year after the events of the Gamma Project and Dr. Wily's overtaking of it and his supposed demise, Dr. Light receives a letter from a mysterious Russian scientist named Dr. Cossack claiming that he is the superior robot engineer in all the world. Cossack states further that he will unleash his army of robots upon the world as a "test" for Light to see which of them is the best. Light calls upon Mega Man from his search for Wily to go after Cossack's Robot Masters.