In this game, the player controls a spaceship in order to explore a base and destroy it. First, the player choose his way on a map. Then the spaceship starts to run on a wall and arrives on different rooms. Each room presents a reactor and enemy spaceships. The player has to destroy quickly every spaceships as the reactor starts to become bigger and bigger. If the player takes to many times the reactor blocks him. If the player arrives in the central room, he can drop a big bomb. Then he has to quit the base before the explosion. The best way is to go back by following empty rooms. Because there is not enough time to clear other rooms. If some reactors fill some rooms, it is possible to across new rooms by avoiding spaceships' attack with the magnetic shield. But it is the last way for the player to escape from the base. During the game, the player has to use a drill in order to open magnetic doors in order toreach the different walls.
The gameplay of this game is maybe inspired by "Reactor" (1982). Cosmic Chasm has inspired the flash advergame "Le grand Sortilège" (2003).
Distribution : Retail - Commercial Platform(s) : Vectrex