Descpription:
Space Invaders is a two-dimensional, fixed shooter game
in which the player controls a laser cannon by moving it horizontally
across the bottom of the screen and firing at aliens.
The aim is to defeat five rows of eleven aliens, some versions feature
different amounts that move horizontally back and forth across the
screen as they descend towards the bottom of the screen.
The player defeats an alien, and earns points, by shooting
it with the laser cannon. As more aliens are defeated, the
aliens' movement and the game's music speed up.
Defeating the aliens brings another wave that is more difficult;
a cycle which can continue indefinitely.
The aliens attempt to destroy the cannon by firing at it while
they are approaching the bottom of the screen. If they reach the
bottom, the alien invasion is successful and the game ends.
A special "mystery ship" will sometimes move across the top of the
screen and will award bonus points if destroyed. The laser cannon is
partially protected by several stationary defense bunkers, the number
varies by version that are gradually destroyed by alien fire.
