SPACEINVADERS(6)                 Games Manual                 SPACEINVADERS(6)

NAME
     spaceinvaders - The famous Space Invaders game

SYNOPSIS
     spaceinvaders [-hlsv]

DESCRIPTION
     This is a curses-based version of the Space Invaders game.  The object of
     the game is to prevent the aliens to invade you.  For that you need to
     destroy all fifty-five aliens before they can land on your floor.

     The game control keys are as follows:

           <cursor-left> / h      move laser base left
           <cursor-right> / l     move laser base right
           <cursor-up> / <space>  laser base shots
           p                      pause/resume game
           q                      quit game

OPTIONS
     -h      Display options help.

     -l      Display high score list.

     -s      Silent mode (don't beep).

     -v      Display program version.

PLAY
     At the start of the game, your laser base is located under the left of
     the four shields which protect you from the aliens missiles.  Above you
     are fifty-five aliens of three different types.  The top row consists of
     eleven aliens which missiles destroy one shield element with one hit.
     The middle two rows consists of twenty-two aliens which missiles destroy
     one shield element with two hits.  The bottom two rows consists of
     another twenty-two aliens which missiles destroy one shield element with
     three hits.  Your laser shot can also damage the shields with the same
     strength as the bottom row aliens do.

     All alien missiles require just one hit to destroy your laser base and so
     does your laser shot do for any of the three different alien types.  When
     your laser shot crosses an alien missile, they'll either pass through or
     they destroy each other.  The aliens start to lower the screen from the
     left to the right and back.  The less aliens exist, the faster they move.
     If the aliens reach the shields, they will start to remove them by their
     movement.

     The game consists of ten waves.  At each new wave the aliens will start
     one line lower.  You win a wave if you destroy all aliens, which brings
     you to the next wave, keeping your previous score.  When you win all ten
     waves, the game starts over at wave one.

     The game is over if the aliens land on your floor (invasion), or destroy
     all of your lives.  You have three lives in total, plus one extra live
     which you will receive at a certain score.

     Sometimes a mystery ship will pass the top screen.  If you are able to
     destroy it, you will get extra points.

SCORING
     Destroying a top row alien gets you 30 points, a middle row alien 20
     points, and a bottom row alien 10 points.  Destroying a mystery ship will
     get you either 50, 100, 150, or 300 points.  If you have reached a score
     of 1500 points you will receive one extra live.  The high score ends at
     9990 points.

ENVIRONMENT
     $LOGNAME                     Name displayed in high score file.

FILES
     $HOME/.spaceinvaders.scores  High score file.

HISTORY
     Space Invaders is an arcade video game created by Tomohiro Nishikado and
     released in 1978. It was originally manufactured and sold by Taito in
     Japan.  Space Invaders is one of the earliest shooting games.

     This version of the game has been developed in 2017 as an homage, trying
     to retain the original game rules as far as possible.

AUTHORS
     Marcus Glocker <marcus@nazgul.ch>

OpenBSD 6.1                      June 7, 2017                      OpenBSD 6.1