Aliens have infested the earths orbiting solarpowerplatforms with power-draining plagues.
Your mission is to destroy those plagues with an power orb by touching them while avoiding enemy fire.
You steer the orb with your mouse and try to destroy all plagues by touching them.
While doing this, you must be careful not to fall off the platforms.
Also you have to avoid getting hit by enemy spaceship fire.
You have some shields, that you can activate with left mouse click, to protect you from enemy fire.
Occasionally you will find extra lives and additional shields on the platforms.