Gameplay
The game is reminiscent of the System Shock series in terms of gameplay. The player must explore the base in order to find items which is needed to establish a line of defence and ultimately escape the installation. This involves fighting off the invading enemies by deploying the defence turrets effectively and using the installation's computer terminals (called "VOS terminals") in order to hinder the intruder's advance.
The computer terminals in the game offers an unusual wide range of interaction. Players can use them to remotely control the defense turrets, load ammunition and inspect the turrets for damage and deploy combat droids within the installations perimeters. Doors can be controlled from the VOS terminals in order to control access to the installations different areas. The player can use this capability to lock in enemy forces in parts of the installation.
The game also allows the player to fight the invaders by shooting them, but this is discouraged by the fact that new enemies arrives with each passing wave of attacking ships. Also, any fighting in the installation greatly degrades the air quality in the immediate area once an enemy is destroyed. The computer might even seal doors to polluted areas, sometimes trapping the player. The player can dissolve the pollution by opening doors to adjacent areas, and the pollution levels can be monitored in the VOS terminal's environmental module.'
The installation is huge, consisting of two major towers with seven floors each (the administrative and domestic blocks), three hangars, a service level, six turrets and a control room. All these are linked by a subway-train like transportation system named "LIMO". Several elevator systems also connects the different levels. This complex layout enables the player to avoid enemies by choosing an alternate route to his/her destination.
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