Alien invader

Hi guys, this is my entry to the Sci-Fi & outer space skin contest, i hope you like it:)

For those with non preview:

Story:
While everyone on earth was living a peaceful life in harmony, the aliens from Mars observed them. As no one on earth ever could imagine a creature that was stronger than them, living this close to their planet wasn't afraid. The Martians had studied the human being for centuries and finally began their plan for extreme elimination of the human beings. Soon, big spaceships from Mars appeared in the atmosphere of earth. Now, earth is in full controll of the Martians who want to keep the planet and terraform it to another red planet.