Neutroid © 1983 Fun Division.
In Neutroid, you are at the controls of a small atomic particle accelerator or synchrotron. In it, Protroid and Antitroid particles appear. Bonus energy regions, high energy walls and deflector rods exist. The aim? Control the movement of an atomic particle called a Neutroid within the synchrotron and neutralize all the orbiting Protroids before your Neutroid becomes energy saturated. Your Neutroid starts off slow and in a low energy state but as it gains energy, its speed increases till it finally reaches the high energy state where controlling it requires a high degree of rapid strategic thinking and lightning fast reflexes.
The author of this game was inspired to write Neutroid after reading an interview with Tim Skelly, the author of the 1982 Gottlieb arcade game Reactor.