ATiP writes: "Fieldrunners belongs to a genre of games known as tower defense. The general idea is to build a maze of defensive structures that will destroy enemies that pass by. And the enemies are generally pretty dumb; they'll follow any path you create for them. Thus, the challenge of the game usually comes from a good mix of enemy types with varying defensive vulnerabilities along with the right mix of offensive weapons to destroy them. Fieldrunners does a good job delivering this balance, forcing you to think about your choices rather than just build without thought."