$20 Game of the Week: Defense Grid – The Awakening (Xbox Live Arcade, PC, Mac OS)

While most other independently developed games feature a quirky art style, Defense Grid features high production values and an interesting twist on the tower defense genre. Designed by Age of Empires 2 lead designer Mark Terrano, Defense Grid is an easy-to-play tower defense game which makes use of the Gamebryo engine (used in Elder Scrolls Oblivion and Civilization IV among other titles). You team up with a sentient computer artificial intelligence in order to thwart an alien invasion. You place a variety of towers, and as needed you can upgrade them provided you have the right amount of resources. Space on the grid is limited, so it’s up to you to figure out what towers to place and how to place them. The base game has only 20 levels, but you can replay them in challenge mode. There are also map packs available for .99 each which extend the game, although it would really benefit from a level editor. On Steam, you can purchase the game and all the map packs for $15 making this a good value. Defense Grid is a fun and addictive game, and at its low price, it almost manages to give most full-priced games a run for their money.