## Description
An easter egg is often just one more program tossed in to a cumbersome mix of
other programs; in this case, the German developers of the StarOffice
application suite (later to be bought by Sun, further developed and given away
for free as OpenOffice) threw in a clone of _Space Invaders_ that could only
be invoked through its Calc (spreadsheet) application.
The game plays as one might expect, the player keyboard-controlling the left
and right movements of a ship at the bottom of the screen as well as directing
when it fires upward — hopefully to hit aliens overhead, gradually descending
as they glide with menace from side to side of the screen. The aliens shoot
down as well, though the player starts with protective barriers overhead to
hide beneath. Later levels introduce tougher alien opponents, including some
requiring multiple direct strikes to kill and others that appear and
disappear. Unusual play mechanisms here are that the player may have up to
five shots on the screen at a given time, and that player shot and alien shot
will cancel each other out.
In addition to the Space Invaders clone, OpenOffice Calc also knows how to
play Tic-Tac-Toe to a stalemate, a mode which can be activated by entering
`=Game(A1:C3;”TicTacToe”)` into cel A4.
Earlier versions of the applications suite (up until StarOffice 4.0 Service
Pack 2) also included a 3D Tetris game and a Frogger clone (“Froggie”) in
StarCalc and a Pac-Man clone (“Sunnyman”) in StarWriter.
OpenOffice (included games)