Oil Man is a maintenance robot made by Dr. Light that is able to produce a special type of oil from the dispenser on his left arm that can work with any machinery.
Guts Man is a civil engineering Robot Master. He was created by Dr. Light to work alongside Bomb Man for the purpose of land reclamation and construction.
Bombman was created by Doctor Thomas Light for demolition and land development, blasting away debris so that land could be cleared for construction projects, working in tandem with Guts Man.
Cut Man is a Robot Master created by Dr. Light to be a timber-felling robot. He is also very stubborn and has a tendency to not listen to others. He likes kirie and haircuts, and has been known to be extremely bad at the game rock-paper-scissors.
Ice Man was created by Dr. Light to perform human-like tasks under extreme climate conditions. This can be done due to the fact he is impervious to chilling sub-zero temperatures.
Mega Man, or Rockman, came into existence due to the following timeline of events. In the fictional and futuristic year 200X, the robotics expert Dr. Thomas Light (Dr. Right in Japan) worked to create a humanoid robot. This robot would demonstrate an advanced artificial intelligence program that would allow it to make decisions based on vague commands and directions.