King is the main villain from Mega Man & Bass.
King was created by Dr. Wily as a very powerful robot, intended to be a test for Bass, because Wily couldn't understand why Bass couldn't beat Mega Man, even being more powerful than him. However, King betrays Wily and steals his projects for Robot Master, later creating his own army of robots. He proclaims himself the King of Robots, and decides he will create a perfect world for the robots. He invades Dr. Light's lab and also steals some of his projects, so Light sends Mega Man after him, at the same time that Wily sends Bass. Each of them go their own way after King, Mega Man to prove that King is wrong on his way and Bass to prove that he is the strongest. Protoman also goes after him, but is severely injured. Mega Man and Bass both defeat King's army, making their way into his fortress. Protoman appears once again and uses all of his power, managing to destroy his shield. King is defeated and then reveal that it was Wily who created him. Wily then brainwashes him to fight again, this time using a giant mech armor. As he is defeated, he saps out of the brainwashing and helps Mega Man and Bass to flee his fortress, who starts to explode. Later on, Meg Man receives a letter from King, revealing that he is still alive and saying that he was wrong in his ways, deciding to help build a world that is good for both humans and robots. Bass defeats Wily, who reveals that King was meant to test his capabilities, and also that he had plans for a new King, but Protoman arrives at his lab and destroy the plans.