The game is turn-based. The player character starts at the centre of the grid and the robots start at randomly selected locations around him. Every time the player character moves a square in any direction (horizontally, vertically, or diagonally), each robot moves one square closer to him, in whichever direction is the shortest way.
If the player character collides with a robot, he dies and the game ends. However, the robots are also fatal to each other - when two robots collide, they both die, leaving behind a scrap heap. These scrap heaps are also fatal to robots.
The player can also teleport into a randomly selected location in cases where escape is otherwise impossible. A teleportation counts as a move. However, because the location is randomly selected, it is possible that the player teleports right into the path of a robot. In some versions of the game, there is a "safe teleport" feature which the player may use a limited number of times (for instance once per level) and there may also be a close-range weapon which kills all robots within the immediate vicinity, the use of which would be limited in a similar way.
When all robots on a level are dead, the player moves onto another level, with more robots. Traditionally, the number of robots on a level is five times the number of the previous level. .