一款炮塔防守 TD 游戏，界面华丽得一塌糊涂，利用一系列先进的武器，粉碎敌人的入侵，捍卫国度的安全。

FEATURES
* A completely new campaign featuring 20 levels!
* A powerful new commander unit which can level up and gain new abilities as you play!
* Over 20 unlockable turrets, orbital ship weapons, automated drones and abilities at your disposal!
* Customize your weapon loadout in the Armory to match the demands of the mission!
* Stunning graphics & fx - with full high-resolution Retina Display support!
* Endless modes for all maps with online highscores.
* Classic mode allows you to compete for scores in a pure skill-based game mode.
* OpenFeint AND Game Centre supported for achievements, global scores, friends and more!
* View strategic layouts from the leaderboards - see how the best players think (OpenFeint required)
* New exclusive music by the creators of the Sentinel 2 music - Specimen A.
* Completely reworked and revamped game engine.

版本 1.2.5 中的新功能

- A whole new 15 map campaign available for purchase. Features a new commander unit, new enemies, new weapons & turrets and new map features and graphics! This also adds 15 endless maps and 6 new classic maps. 
- Use already unlocked weaponry from the first campaign to help with the second.
** The first two maps and one classic map from the new campaign are available for FREE to whet your appetites! **
- Shortcut purchases have been added for players who want to unlock everything instantly or attain a maximum level commander.
- iPad level backgrounds are now higher resolution
- Endless games now give you far more credits/XP
- Many visual effects have been improved
- Various bugfixes and optimisations