In the early 21st century Dr. Light and Dr. Wily created a series of powerful robots to aid society. From robots built to lift heavy objects (Gutsman) to logging robots (Cutman) and beyond. Unfortunately, Dr. Wily felt betrayed and shunned when his partner Dr. Light received all the glory, recognition and accolades. Dr. Wily became sick with rage at his former friend. He eventually turned on his friend and stole 6 of the robots they worked on. With those robots he began to attack the city he had lived in. Dr. Light watched in horror at his best friend's actions. Finally another robot he had created to be a lab assistant volunteered to be weaponized to fight against Dr. Wily's forces.
The robot, renamed Megaman, was successful in defeating Dr. Wily's forces. But Dr. Wily did not give up. After his defeat he slipped away to the shadows to lick his wounds and rebuild his forces.
Megaman and Dr. Wily's forces engaged in numerous clashes after that with the stakes becoming higher and higher as time went on.
While the fight against Dr. Wily raged on, Dr. Light began to work on a new type of robot. Based loosely off his earlier creation, Megaman, this new robot was a quantum leap ahead in every conceivable way. The principle method of advancement for this robot was to grant him the power of independent thought and will. A machine capable of violating the three laws of robotics if he so chose to. Dr. Light realised the danger of such unrestrained power, but even still could not handicap his creation by removing choice.
Dr. Light knew that if he was to unleash a robot with such advanced capabilities, he would have to come up with a method to thoroughly test his creation's choices and decisions. But Dr. Light knew that such a process would take at least 15 years or more. And given that his health was already failing him, he knew he'd never live long enough to perform the tests himself. His only option was to seal his creation away in a computerized capsule which would test his creation's systems to ensure reliability.
Meanwhile Dr. Wily also knew that his time was coming to an end and decided that if he wasn't able to rule the world, he'd at the very least ruin it. With that in mind he began construction of his own advanced robot. Using knowledge gained from a previous fight involving viral warfare in robots, he developed a powerful new virus to serve as the mind of his robot. This new robot was completed and had the virus uploaded into it, and was set to release… However Dr. Wily died and his robot was never released as planned.
Dr. Light, having completed his robot and sealed it away, eventually died some time after his former colleague. Their lifetime of struggle and violence having ended.
For many years, a relative peace remained in the world. This peace allowed the world to rebuild and develop. And most importantly… forget about the war between friends fought by robots.
Eventually an archaeologist named Dr. Cain stumbled upon the ruined lab of Dr. Light. After excavating much of the ruined section he discovered a capsuled marked “X”. He eventually opened the capsule up and discovered Dr. Light's legacy.
Dr. Cain was fascinated by X. After much time spent with X and studying X, Dr. Cain began to work on duplicating X's designs. While he did not entirely understand X's designs, it didn't stop him from creating more robots based off X's designs. Eventually he dubbed them Reploids.
Within 3 years, reploid production increased and research was being done by numerous companies. Reploids they had become fairly commonplace in the world and society had largely accepted them. But with the increased number of reploids around, problems began to arise. Due to the power of their free will, not every reploid chose to obey the rules and law. These reploids were dubbed mavericks. And the number of maverick incidents began to rise.
Realising what kind of a problem this maverick situation would evolve into if left unchecked, Dr. Cain set up a force, sanctioned (and later fully funded) by the UN, to deal with mavericks. This group was dubbed the Maverick Hunters.