Earth Invasion

Earth Invasion is a collection of three shoot 'em up games presented as missions accessible from a command central.* Earth Orbit Mission is a traditional fixed screen shoot 'em up where the player moves a craft around the bottom half of the screen and shoots at the enemies appearing from the top. The objective of the mission is to reduce the number of enemy crafts that are moving towards the player's planet.

• Ground Mission is played from a side view and resembles Defender with the player being able to turn around and fly both to the left and to the right. The task here is to defend the citizens on the planet's surface while defeating the remaining enemies.

• Deep Space Mission is played from a first person perspective. The enemies are in retreat and the player has to follow them and finish them once and for all. The gameplay is limited to moving a cross hair across the screen and shoot the enemy ships as they appear.

In all games the space ship is equipped with a phasor for basic firepower and a photon cannon that takes out numerous enemies in a single blast. There are also various special weapons (guiding, spreaders, accelerators) which are made available through power ups (auxiliary munitions). Other power ups give additional shield, ammo or points bonuses.