Tower defense games are everywhere. You can find one on every current generation console (including portables), on the internet, even on the iPhone (where they are quite popular). They've come and gone in multiple colorful varieties. Just when I thought I'd seen everything, Comet Crash came waltzing along.
The fundamentals of Comet Crash are still very easy to pick up by anyone who's played their fair share of tower defense games. You control a ship that you can use to move around and survey the arena, and also build and maintain your defenses. There are two cores; yours and your opponent's. Your opponent will consistently spawn enemies that will attempt to attack your core. To stop this, you'll have to build towers to destroy enemy units before they get to your core. Like in any good TD game, towers are upgradeable (range, fire speed, power), repairable, and recyclable, and come in multiple varieties, some being better against certain units than others. For example, the Pulsar fries all ground units quickly and efficiently, but ignores air units and is vulnerable to being momentarily disabled by enemy EMP units, allowing a small group to slip past. Your standard turret is dirt cheap and makes for a nice defensive option early on, but faster moving enemies will slip past them easily enough. Bomber towers are great all around units, attacking both air and ground units with splash damage, but are really expensive to upgrade. Lasers ignore ground units, but destroy passing resource meteors for you and can really cut air units down to size.
But there's one thing a little different about Comet Crash: going on the offensive. In Comet Crash the match ends when you destroy the enemy core, not after a certain number of units have been fended off, or you simply are defeated. You go about doing this by spawning units of your own! Certain special towers act as background factories, quietly building your army while you focus on defending your core. With units at your disposal, you can send out any number of them with a flick of the right stick.
Like towers, units come in many, many varieties, but can be separated into three categories; Offense, Support and Counter-Offense. Offensive units are your bread and butter, simply used to hopefully charge past your enemy's defenses and hit their core. Examples include the basic scout vehicle, which is decently fast and built very quickly, but has very little health. Tanks have more health, but move slower and take a little more time to build.
Support units are designed to help keep your offensive units alive, like the dropship, which can load a couple dozen ground units and then fly right over the enemy's defenses (unless they have anti-air towers), dropping them closer to the enemy core, and the EMP mine, which disables Pulsars for a couple seconds to allow ground units safe passage.
Counter-Offensive units are brilliant, and open up a whole new ballgame of defensive strategy. With a decent store of counter-offensive units built up, you can hold off an entire attack with just a few well placed towers. An example is the Thief, a gigantic ship that at first glance seems to function like an even slower-moving, but more heavily-armored tank. Enemy units that run into it while it's glowing, however, are instantly converted to your side, and turn right around and head back to the enemy base. Then there's the Hammer. It's an extremely slow moving unit, that leaps instead of runs. Every time it lands though, it freezes nearby enemy units in place momentarily, leaving them open to extra turret fire. Needless to say, a squad of hammers and a couple upgraded pulsars can cripple even a ground horde numbering in the several hundreds.
You can have up to 1,000 units ready to mobilize (or already mobilized) at any time. Can anyone say "Unleash the horde"? In later stages, the computer will use armies of such sizes against you, but with some nice tactics and powerful towers, you can hold off even these with relative ease. The importance of support and counter-offensive units in particular becomes surprisingly outstanding midway through the campaign. These aren't just novelties; they're a genuinely innovative way to expand the game's strategic potential. Surprisingly, battles can become really epic and engulfing with hundreds of units on screen, and lasers, bullets and bombs flying everywhere.
In the audio-visual department, Comet Crash is presented simply. The graphics are sharp, and detailed enough that I can pick out a scout making its way upstream a river of enemy units, but most object models are simple almost to the point of slight crudeness. But if this is what makes the game capable of rendering hundreds of them at a time with few signs of trouble, I see no reason to complain. Audio is largely forgettable, composed of the usual moody space themes you'd expect from a futuristic tower defense game (or not).
The campaign is separated into a couple dozen levels that, while getting progressively more difficult and offering up a variety of challenges, also gradually introduces you to each unit and tower, as well as some nice strategies. Impressively, there's also 3-player co-op and 4 player versus (no online), making this surprisingly acceptable as a party game. If you like your games with a double-helping of strategy, I don't see why you wouldn't like Comet Crash. An 8.5/10