Reactor is a raster video arcade game released in 1982 by Gottlieb. The object of the game is to cool down the reactor core without being hurled by magnetism and repulsion by enemy swarms of nuclear particles.
Reactor was developed by Tim Skelly, who was also responsible for Star Castle and Solar Quest. It was the first arcade game to credit the developer on the game’s title screen.
The player controls a cursor that can move freely within a screen-sized arena, the nuclear reactor. The center contains a sun-type gravitational power source, the slowly overheating reactor core. The surrounding wall or the sun, if touched results in death. The cursor is controlled with a trackball by the player, who has to roll it fast in one direction in order to overcome the momentum of gravitation imposed by the sun. Swarms of enemy objects named after various radioactive particles float around in the reactor arena, obeying simple physical laws. These enemies can freely bounce into the walls at low speeds, have a repulsive force against each other and actively attack the player cursor. Boss types often break up into several smaller particles.