Play online Mars Colony TD here on vitalitygames. After several decades of research, experimentation and trial and error, man has finally managed to make Mars habitable. Unfortunately, the aliens leaving peacefully on Mars are not too happy with their visitors and are looking to destroy you. Set up a powerful tower defense to maintain control of your land. The humans have finally established a settlement on Mars. But the red planet is under alien attack. Place defense towers to stop the invasion. People have finally managed to create columns of Mars. But unfortunately there is not safe and is full of aliens. You have to try to defend the towers of an alien invasion. Have fun!