In the year 2018, what initially appears to be a comet crashes into Baghdad with seismic force. Just like that, Earth has been invaded. Anomaly: Warzone Earth tells the story of the brave members of the fourteenth platoon, the military group that responds to the disaster first and (with any luck) the group that will still be around to fire the final shot.
Anomaly: Warzone Earth is a tower defense game in reverse. As events unfold, aliens have set up encampments and Earth's soldiers are the new invaders. Towers and turrets dot the landscape. Extraterrestrial vessels hover over scorched soil and the remnants of apartments and office buildings. The loss of human lives is palpable. Now soldiers must take back each captured zone by bringing the fight to the aliens.
Aside from the offensive approach, these power-ups are the game's most significant twist on the familiar genre. When an enemy tower is leveled, space is cleared and an icon appears that the commander can collect and utilize. These allow him to deploy a field of fog that forces enemies to fire blindly, or place decoy units or repair damaged vehicles. Air strikes are also possible later in the campaign. Careful resource management and planning are constant imperatives. If units are frequently annihilated, slight changes to the route they follow and the order of power-up deployment can make a substantial difference.
At first, Anomaly: Warzone Earth seems to do everything well, but some weak elements detract from the otherwise exemplary experience. The low number of unique units is disappointing, particularly since it's possible to clear most scenarios by upgrading a couple of Crawler units and letting a Shield unit accompany them as they lead a merry procession through enemy territory. Meanwhile, in typical tower defense fashion, enemies generally remain stationary at key posts rather than putting up a real fight. The player will see a few "Game Over" screens after making the occasional silly mistake, but frequent checkpoints throughout the campaign prevent much lost progress.
Completing the primary campaign unlocks alternate modes that present new ways to play. For instance, the Baghdad Mayhem mode offers a battlefield with limited resources and then challenges the player to survive 18 enemy waves while destroying key targets within a strict 5-minute time limit for each wave. The Tokyo Raid mode features a similar setup with a new mandate: cross a series of bridges before they explode. Most of the additional modes are frustrating, though, because they lack checkpoints. If a player spends 40 minutes working through half of 18 stages and then fails, that's a lot of time down the drain. There are also six Tactical Trials stages, thankfully, that provide new challenges in smaller portions. These stages are memorable because they require more creative resource management. It's a shame that there weren't more of them, as they provide some of the game's most memorable moments.
Anomaly: Warzone Earth provides some good incentives to keep playing, notably its well-implemented difficulty settings. The player can choose a preferred setting before attempting each individual stage, rather than committing to one setting and finding that it grows too difficult or too easy halfway through the campaign. Medals for ruthless or efficient play provide further incentive to replay stages, and leaderboards make it easy to compare performance with close friends or worldwide leaders.
It doesn't hurt that Anomaly: Warzone Earth is also a surprisingly pretty game, particularly given its subject matter and its availability as a rather small downloadable title. Units are easy to distinguish from one another; the ruined cityscapes are chilling, with palm trees swaying as spacecraft fly overhead and dust swirls around the gutted buildings and crumbling asphalt. The haunting soundtrack doesn't stand out, but it suitably accompanies the stages. Voice acting is similarly competent, though the actors tear through some strikingly bland conversations as they help weave the game's generic story.
A good tower defense game is an addictive and beautiful thing, and Anomaly: Warzone Earth is no exception. It offers a couple of twists on the familiar formula, but more variety and perhaps a few more missions could have pushed it over the top. Even though the included content falls short of some of its most excellent peers, there's still plenty here to keep players entertained for a long time as they prove to the nasty aliens that Earth is the wrong planet to invade.
This review is based on the final release of the Xbox Live Arcade version of Anomaly: Warzone Earth, provided by Microsoft.
Jason Venter is a freelance game critic and the founder of the community reviews site, HonestGamers. You can follow him on Twitter at @jasonventer.
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