: Defense Grid

: Defense Grid: The Awakening

You thought this planet was abandoned. You were wrong. Well, from a certain point-of-view: a computer that calls itself Entity is now in control of this inhospitable chunk of rock. Luckily, it’s benign. Unluckily, an alien invasion force has arrived, and Entity’s defense grid is offline.

“Ah, the aliens are back, are they?” Entity asks in a nonchalant voice as you scan your surroundings. “Yes, well, we knew this day would come, and so it has,” the computer adds, as if it’s talking to a long-lost friend. There will be time for a round of “How do you do?” and raspberry tasting later; you have work to do.

The Rub

The objective seems simple enough: place towers along the aliens’ path and blast them to smithereens. At first you only have access to basic gun turrets, but soon Entity provides others to choose from, including cannons, flame-throwing towers, spinning structures that slow down enemies, and more. As you gain resources from eliminating aliens, you can upgrade existing towers with more powerful attacks and wider ranges of fire, or buy new ones. Do you want to inflict a few devastating blows, or death by a thousand paper cuts?

Of course, the aliens come in 15 different varieties, each with unique movement rates, levels of shielding, degrees of strength, and other qualities to consider, so you can’t simply place a series of gun turrets and sit back to watch the carnage. Some of the aliens even fly, and certain weapons are useless against them.

The aliens want your power cores, and if they carry all of them off the map, they’ll prevent the defense grid from going online. Wise tower defense strategists would be wise to heed Entity’s advice: “Be merciless. They are.”

Tips and Tricks

• When you place a tower, it takes a few seconds for the structure to rise out of the pad, so make sure you’re not relying on it to take out a final alien that’s about to exit the map with a power core.
• And when you upgrade a tower, you need to give the process several seconds: the old tower lowers out of view, and then the new one rises. Your best time to do that isn’t when you need that tower to destroy some aliens in the next few seconds.
• Pay close attention to towers’ ranges of fire: place the ones with smaller ranges closer to the path, and let the long-distance guns sit back. Meteor towers are perfect for out-of-the-way spots, since they can cover long distances.
• You can click on an alien to check out its stats and monitor its health level. That’s a handy way to know if you should beef up some last-minute defenses before it reaches the exit.
• Make sure you’re prepared for boss aliens when they arrive. (The bar along the top of the screen tells you what types of enemies are on their way.) Because the bosses are so powerful, you won’t earn many resources for a few minutes while your existing towers work on taking them down.
• You’ll need quick mouse moves to survive the game’s higher levels. From the main menu, select Help and Options, then choose Controls. The first tab lets you change the mouse sensitivity: fill the bar to let your cursor move as fast as possible around the screen; empty it for the slowest speed. You can choose anything in-between to fine-tune the setting, but note that you won’t see the effect of your choice until you resume gameplay.
• Don’t place temporal towers where their ranges overlap each other; they seem to cancel each other out.
• Each tower or group of towers has a force field. Aliens must go around the force field, unless their path is completely blocked. Keep this in mind as you look for ways to lengthen the aliens’ path; the farther they have to go, the more opportunities your towers have to shoot at them, and the longer it takes for them to get away with power cores.