Defense Grid: The Awakening

For those of you who don't know Defense Grid is a tower defense game available on through Steam and XBL Marketplace. You play one of the last people alive on your planet after a series of brutal alien attacks. You must fight off the alien invaders though 20 missions in total. Starting with simple tutorials which let you learn the 10 different type of turrets at a comfortable pace and ending with ball breakingly frustrating levels. I've really enjoyed this game, it will take you a good 4 hours to get through if you're a skilled player, but where the game really shines is it's re-playability.

After each level you're graded by either a bronze, silver or gold medal. Getting gold is really challenging and requires you to play the level almost perfectly. Making sure you're poisoning each tower for maximum effectiveness isthe key to saving your resources which is what you need for that all important gold medal. The Leader Board is also another way the game will suck you back in. Not only can you compare scores with friends over steam but it will also give you a world ranking. Replaying levels to squeeze out a few more points and go up a few more ranks is an addictive process witch will take many more hours from your life.

The story mode of Defense Grid is enough to keep you entertained for the price. The game still feels the need to out do it's self by having additional modes:

Story challenge
is the same as regular story apart from the invading aliens are much
harder to kill, this may force you to rethink strategies on levels you
once breezed through.

Practise
starts you off with 40k resources (quite a lot) and gives you time to
look at the level and figure out key placing of towers and which will
be best to upgrade without the tension waiting to collect resources
brings.

Grinder is a
really fun mode. Just like story mode you start off with a small amount
of resources and you collect more as you kill the invading aliens. The
twist is there is only one type of alien invader which comes in
increasingly larger sized packs for 99 waves.

Tower Limit
You're only able to build a set amount of towers.

Overall the game
is balanced with a good range of aliens and turrets each with there own strengths and weaknesses. You'll be forced to use all types of turrets to make it though the tougher levels, but none so more than the Meteor turret which is really quite over powered. It's range covers almost the entire map by itself and it deals an insane amount of damage. If you can manage to hold off the beginning waves
you'll find yourself placing meteors everywhere. Luckily though the game never gives you the opportunity to horde your resources to set up a meteor farm. Another criticism I have is with grinder mode. If you've managed to hold back the attackers for the first 20 waves you'll find yourself with a crazy amount of resources, when this happens you'll have such good defenses that the next 60 or so waves won't really stand a chance. This leaves you with your finger on the fast forward time button for an uncomfortable amount of time.

I highly recommend you check out this game, there is a demo available on steam which won't take long to download, but will leave you wanting more. So go ahead and check it out!