- M121 Mason is a character from the Generation One continuity family.
M121 Mason is a Microman scientist who researches natural phenomena. The Micromen are 10 centimeter aliens from the planet Micro Earth. He appears to have a variety of energy-related abilities, producing energy spheres and an energy shield in battle. Mason is also equipped with a jet-pack and wields a blaster of variable strength. Finally, he can summon the giant robot Robotman during battle, riding in its chest while it's active.