Anomaly: Warzone Earth is described as a "tower offense" game. It has been a success on many platforms, first on PC and Mac, then for iOS devices, Android, and finally on Xbox Live Arcade last spring. One thing was missing from the package, though: co-op. The Playstation Network release fixes this oversight with the inclusion of a co-op mode for two local players. So how does the "tower offense" work exactly, anyway, and does the co-op make the experience better, or worse?
The tower defense genre is relatively young, but many different spins and twists on the genre have come along. We've had FPS tower defense, third person action tower defense, static map style, maze building style, and even undead against flora. Anomaly: Warzone Earth takes the standard formula and holds a mirror to it. Instead of placing towers to hold off the invaders, you are on the attack, taking down the defending towers. It's an innovation that takes some getting used to, but it's very rewarding as a result.
In the standard tower defense game, there is a goal that must be protected. Defensive towers slay the typically unintelligent invaders, earning currency which can be spent for more and better towers. The key to the typical tower defense game is to maximize efficiency by creating chokepoints and exploiting key areas. Anomaly: Warzone Earth reverses this; you control the invading force, and must look for the weak points in the defensive structures in the maze. By choosing the literal path of least resistance, you can ensure the survival of your small forces, earning credits to upgrade or buy new units. By spending wisely and commanding your forces well, you'll be able to destroy everything in your path from start to finish.
The storyline in Anomaly: Warzone Earth is very basic: Earth has been invaded by an unknown force of alien origin. The aliens have scattered towers across major cities, for who knows what purpose. It's not much of a narrative, really, though the opening cinematic is quite well done. Fellow soldiers narrate the action, letting you know what's going on while you fight. The production values are very good throughout, with nicely detailed citiy environments and slick looking units on both sides of the war.
Most levels begin with purchases. It's important to choose wisely, as credits are very hard to come by. Rarely will you have a tremendous army at your disposal. Instead, most of the time, you'll be using only a handful of units. You'll be using APCs and Tanks as damage sponges, while glass cannons like the Crawler and twin flame spouting Dragon dish out the damage. Perhaps the most valuable unit is the Shield Generator, which gives a regenerating damage shield to nearby units. Exploiting the different capabilities of these vehicles is a key to success.