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Games on the Go: Tower Defense

It's been said that the best offense is a good defense, and the Tower Defense genre certainly bears out that proverb. Tower defense games involve strategically positioning immobile defensive units on a map in order to keep an ever-increasing swarm of enemies from reaching your "home base." Players must consider both careful unit placement and smart resource allocation, as units can generally be upgraded, thus increasing their attack range and power. A good TD game becomes a steadily intensifying test, requiring the player to juggle multiple tasks while preparing for the next wave of baddies.

The genre evolved from custom maps created for real-time strategy (RTS) games like 'Warcraft III.' In fact, Tower Defense games often feel like stripped down and frantic real-time shooters, making them perfect for quick bursts of Internet time wastage. The genre has, however, carved out its own niche over the past few years, with bona fide console classics like 'PixelJunk Monsters' on the PlayStation 3 and PlayStation Portable (PSP). For those new to the genre, or looking for a way scratch their defensive itch, here's our list of our five favorite downloadable and flash-based Tower Defense games.

Plants Vs. Zombies

plants vs. zombies
We can't talk about the genre without mentioning PopCap Games' entry, which helped to redefine what a Tower Defense game can be. It's absolutely fantastic, but perhaps a little too good, as it took all our strength to pry ourselves away from it to write this article. 'Plants Vs. Zombies' features a uniquely horizontal playing field, tons and tons of cleverly plant-themed units, a horde of entertaining zombies (particularly when the Thriller zombie shows up), and that certain something that keeps you playing well into the wee hours of the night. Pro tip: Place Potato Mines behind a Wall Nut to catch pole vaulting zombies off guard.

Revenge of the Titans

revenge of the titans
Playing 'Revenge of the Titans' gives us plenty of flashbacks to hours spent with RTS classics like 'Dune II' and 'Warcraft.' Featuring large scrolling maps as well as resource gathering, Revenge of the Titans comes close to being an RTS, yet it stays firmly rooted (no pun intended) in the static game play of Tower Defense games. Its stylish presentation juxtaposes gloomy, bombed-out landscapes with cartoonish enemies, and it features a deep research element, allowing players to spend their hard earned space bucks in myriad ways, from improving gun turret's reload times to increasing the strength of defensive blockades. We've become so addicted to the demo of 'Revenge of the Titans,' in fact, that we can definitely recommend pre-ordering the full game.

Cursed Treasure

cursed treasure
'Cursed Treasure' puts a 'Dungeons & Dragons' spin on the genre, throwing leveling up and a fantasy setting into the mix. With the help of undead crypts and fire-spewing temples, players must keep reckless heroes and adventurers from stealing their precious gems, and careful unit placement is absolutely crucial to succeeding. Experience points are used as currency for unit upgrades, but, uniquely enough, players retain experience even if they fail a level. This comes in handy during the harder levels, letting us continually retry until we upgrade our weapons enough to keep those pesky heroes from stealing our jewels.

Desktop Tower Defense

desktop tower defense
This is the game that, while not creating the Tower Defense genre, certainly brought it into the limelight. It's been played over 15 million times in the three years since its release, and is available in myriad languages. While it is the essential Tower Defense game, 'Desktop Tower Defense' (literally set on a computer desk) differs from many others in that, rather than limiting enemies to a predetermined path towards your "base," the game requires you to play mapmaker, positioning defensive units in order to control the enemy's progress.

Vector TD

vector td
The bare bones, geometric shapes and grid-like structure of 'Vector TD' make it feel like the 'Tron' of Tower Defense games. While it strips away the graphical pleasantries of some other games, it still has a style and game play of its own. It can take a second to get acclimated to the menu setup, and we suggest turning off the horrific trance soundtrack (although you can always turn off the lights and pretend you're hacking the Gibson), but overall it provides a unique Tower Defense experience.

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