In The Fortress V1, your main objective is to destroy the wonder on the island in the middle of the map. All four players team up and fight to the sound of cool music. Note that you must make the computer player Oranos for the best possible eye candy. For added fun, you can turn off locked teams and attack your allies when they're off on "crusade".
I think the map is a little too large. 2MB is going to take forever to transfer on ESO. Make it around 1 MB so it doesn't take 10 minutes for people on ESO to download.