Defend the Earth from an alien attack! The earth is under attack by an alien force, which is sending wave after wave of asteroids hurtling toward the surface.You are the last line of defense, piloting the new upgradeable asteroid defense system.Touch the screen to fire your cannon, the platform will track your movements across the screen.The minerals in the asteroids will allow you upgrade the platform to deal with the increasing threat of later stages. Including placing automated turrets. 【基本信息】 作者：Google Play提供 更新时间：2013-05-17 版本：1.2 系统：Android 2.0以上 语言：英文[详情]
