Systems and methods for hosting a game are disclosed in which a user is granted a first base comprising a three-dimensional section with a base target. Game credit is earned through successful completion of campaigns in which the user, posed as an avatar, fights against a plurality of defendants of a second base in a three dimensional action format in which the avatar and the plurality of defendants use weapons against each other. The user is provided with a description of base upgrades, including three-dimensional pre-fabricated sections that can be dynamically added to the first base, and associated costs for the upgrades. Upon selection a base upgrade, the associated cost of the selected upgrade is deducted from the game credit accrued by the user. The first base is augmented with the selected base upgrade thereby augmenting a defense of the first base.