Xurge [$0.99] doesn't try to wow you with a particularly deep gameplay experience or with awe-inducing graphics. Rather, Xurge is one of those retro-style games that seeks to get you hooked on simple gameplay that becomes progressively more difficult and challenges you to simply get better at what it offers. As far as simple arcade games go, Xurge does a good job of hitting its mark.

Xurge doesn't bother trying to create any kind of story to serve as a backdrop to your gameplay. You can discern that there are alien invaders attempting to take over your planet, and the only thing between them and world domination are your four cannons. Obviously, the goal then becomes to take out all the invaders with said cannons before the intruders take them out. Before a cannon can be fired, however, you must tap on it to prime it. Once primed, taking a shot is as easy as pressing the big 'Fire' button on the screen.

To further complicate matters, your cannons can be primed in two different modes, each designed to take out different colored enemies. In addition, random bombs will be coming down on the sides of the screen, which must be destroyed by tapping on them. Aiding in your planetary defense are power-ups that occasionally appear after taking out certain invaders. Power-ups range from increased firepower to a slow mode, and can provide a short-lived advantage.

All these elements lead to a certain situational awareness that must be kept in order to last long in Xurge. Not only do you have to make sure that the right cannon is primed, but you have to make sure it is in the right mode and firing correctly. As the later levels increase the tempo (and variety) of the baddies, gameplay becomes frantic, but still enjoyable. One complaint is in the delay between tapping a cannon and having it primed, but I believe this is a deliberate choice to add some tension to the later parts of the game when precision and speed are essential to survival.

Xurge seems to embrace its retro-inspired feel in all facets, and does a good job doing so. Everything from the 16-bit pixelated visuals to the catchy MIDI-esque music screams nostalgia. More importantly, the 16-bit heritage does a good job of complementing the overall feel of Xurge, rather than being any sort of hindrance to it. Of course, if pixelated graphics aren't your thing, then odds are you probably aren't going to appreciate the artistic style of Xurge.

If you're a fan of retro-themed titles and are looking for a new arcade game, Xurge isn't a bad choice to check out. It combines a simple, yet enjoyable gameplay experience with longevity features such as achievements, Game Center and OpenFeint support, and a fair amount of difficulties and game modes. Sure, the gameplay is a bit basic, but what it does offer is executed well.