Click Defense

In the Click Defense tower defense game you are in a distant galaxy in far away space.  The evil emperor and his green hordes have been attacking the other planets and now they have set their sites on your planet.  You need to defend your base if you want your planet to survive.  Fight off the green invaders as they descend on your base.  Kill the bosses and collect rubies and power ups to make your tower defenses even stronger.  Your planet it depending on you.