Those sages of the turntable, the Beastie Boys, once quipped, "If you want to battle you're in denial, coming from Uranus to check my style."
And so it is that the tower defence genre goes Intergalactic Planetary. Indeed, spherically Intergalactic Planetary.
The backstory to Star Defense sees humans expanding into space and butting up against an aggressive alien race known as the S'rath. They turn up the heat on half a dozen colonies.
But no need for your knees to start shaking and your fingers to pop because you have an arsenal of defensive turrets to beat back these extraterrestrial bad boys.
Beginning with the easy 20 waves of Outpost D-13 and concluding with an epic 60-wave battle on Magna Prime, your objective is to preserve your mining base's ten shield wall hit points. Every enemy that makes it to the mining base alive nicks a point from the shield.
On each of the spherical planetary colonies, S'rath forces makes their way from a drop ship to your mining base by way of a set path. This byway snakes atop the surface of each colony, making it easy to deploy turrets along the edges.
You do this by sliding a finger from the turret menu lining the right side of the screen to the spot upon which you wish to build. It's instantaneous: slide your finger from menu to map and a turret is immediately plopped down, firing as soon as it's in place. The controls are precise and intuitive, the camera effortlessly moved through three-dimensional space via multi-touch and turrets placed with a flick of a finger.
Turret economics provides Star Defense with its first layer of strategy. New turrets are more affordable than upgrades, though less effective on the battlefield. Enemy resistance to bullet, fire, or electrical attacks also influences decision-making. It might be cheaper to plunk down a Plasma turret to deal with a wave of Drones than saving up for a Quantum Launcher upgrade, but it could hurt you in the next round when a fire-resistant Viceroy scuttles across the map.
Success in Star Defense is dependent not just on what defences you build, but where you build them. Each stage's maze-like pathways must be exploited to maximise the area covered by each turret. Plopping down defences haphazardly in lines along the highway delivers nothing but loss; instead, you have to take advantage of bends and corners so that turrets get two or three chances to fire on any creatures that walk by.
The need to balance the concerns of economy and real estate make Star Defense strategically challenging. Excellent gameplay balancing ensures that each turret has value. You can't simply buy a line of Gauss turrets and expect them to wipe out every enemy that trundles along; rather, you're forced to contrive strategies that deal with a wide range of foes, fit within your budget, and leverage the available space.
Three levels of difficulty and an array of achievements (referred to as commendations) provide some replay value, although Challenge mode offers more incentive to keep coming back to Star Defense. Here you're pitted against a never-ending series of enemy waves, your high-scores posted to Facebook or Twitter. Opening this mode to include additional levels would be nice, as would incorporating new objectives and bonuses for going back and replaying levels in the campaign.
Neither diminish the satisfying strategic gameplay awaiting you in this stellar-looking title, though. Like a pinch to the neck of Mr Spock, Star Defense takes out competing tower defence games with gorgeous visuals and equally fine-tuned play.