ZDefense is a vector-drawn, hexagonal, free-form tower defense game, and the towers can be upgraded (straight-path upgrades) to phenomenal potency. As with most free-form tower defense games, you are disallowed from cutting the invaders off from their goal; however, the game is played on a hexagonal map, and as the game progresses, some of the spaces have special attributes, which provides dynamic challenges to the player. The game has a tutorial, and features three levels of difficulty. The third level of difficulty is customizable: Basically, you decide just how difficult you want it to be. ZDefense also sports a level editor and a built-in screengrabber.