Yet another legendary, genre-defining game – in an era replete with genre-defining classics – in which a single player takes control of a ship trapped in the middle of an asteroid field. A number of large, slow-moving asteroids drift randomly around the play area and must be shot by the player. When shot, the asteroids will break into a number of smaller pieces, which must also be shot until, eventually, all of the asteroids and fragments will be destroyed and the next wave begins. Asteroids introduced real-world physics to video games for the first time, with speed and inertia all adding to the player’s problems. As well as the inertia of the player’s ship – forcing the player to allow for the ship slowing down and speeding up whenever the thrust button was utilized – shot asteroids would often send fragments flying in seemingly random directions, and at varying and unpredictable speeds. As well as the ever-present asteroids, alien saucers also make a regular appearance. These move diagonally around the screen, firing at the player’s ship and must be quickly destroyed.