The colonists are under attack! Construct towers with gun turrets to defend them from the alien attacks. Research better habitats, mining facilities and weapons to give your civilization the advantage. The game's construction system is block based, making it fresh and easy to manage. The vertical tower defense style seems to work out very well.

Select the a block from the bottom panel and place it using your left mouse. You can research more block types and arrange the construction bar in the menu between each battle.