Instead of the tired old formula though, it incorporates some really interesting strategy elements that you typically don't see in Flash games this small and simple. You play the commander of a massive battleship, or some sort of deep-space warship. (I preferred to think of it as my very own Battlestar JIGtactica—some of the mechanics are eerily familiar.) The story isn't too clear, so don't expect some epic, Hubbard-esque space opera. The long and short of it is that you're alone in space, forced to defend yourself against waves of hostile aliens.
Your ship begins with just a main cannon (the Ultragun) and a single fighter (a much smaller ship that pilots itself, patrolling in front of your battleship). The main cannon is the only weapon that you directly control (mouse to aim, click to shoot). Destroying enemies earns currency called "RU", which is used to buy more weapons, ships and upgrades. This is all done through in the build menu, accessed by pressing [Space]. You're shown a diagram with over a dozen "build points" all over the battleship. Click one of these points to bring up its menu, and you get the option of building one of three different turrets; a rocket launcher, laser gun or flak cannon. Each has its own strengths and weaknesses, but you can upgrade various aspects like range and damage to compensate.
As mentioned, the only gun you control yourself is the main cannon, which can also be upgraded. At first, I was a little bummed about this, but after a while it turned out to be a blessing. When things get heavy, you'll be glad you've got gunners controlling all the other turrets. Fighter ships and repair drones are your final resources. The little fighter ships swarm around and do a decent job of slowing the enemy down if they're upgraded. You have four launch bays total, three of which need to be built before you can use them. The repair drones (also upgradable) are even more important, since you'll need them to come out and fix your ship and turrets when you're getting pounded.
Analysis: Orbital Decay is broken up into a half-dozen levels or so. Enemy ships gradually enter from the right side of the field, first appearing as little radar blips. They come in waves of increasing intensity, similar to a tower defense game. In fact, I found myself drawing more than one similarity to the tower defense genre, which I thought was pretty interesting, considering it's a side-scrolling shooter. There are many different ways to build your battleship, such as focusing on long-range defense, or opting for in-your-face offense. You can min/max dozens of upgradable aspects of your turrets and fighters to create a personalized strategy.
The gameplay gets a little repetitive after awhile, but the challenge really increases on the hardest setting. There are some crazy-looking alien ships to giggle at, and the on-screen narrator is a nice little retro touch. But if you're not a fan of the old-school graphics, don't count on being the least bit dazzled by its presentation. You might even find the controls a little "old-school," mainly when it comes to aiming your cannon. The lack of responsiveness takes some getting used to. But hey, it's a 1000-ton battleship cannon, so whaddaya expect?
Orbital Decay puts a pretty cool twist on an old genre. Even though the overall package might come across a bit lowbrow, the gameplay can be a lot of fun for the right players. As our wise and poignant Psychotronic mentioned, "It's a unique way for action/defense fans to scratch the itch."