Overview
Zen was the master computer aboard the Liberator (formerly Deep Space Vehicle 2), the highly advanced spacecraft used by Blake and the others initially to escape from and then attack the Federation. Zen's history, like that of the Liberator itself, is unknown prior to its first appearance. It specifically refused to answer questions about the previous crew of the Liberator. It was constructed by "The System" ("Redemption"), which also installed a series of over-rides to take external control of the ship if necessary. It is revealed in Escape Velocity that Zen killed its original human crew who were rebelling against The System (a super computer group mind similar to the Borg in Star Trek). In retaking control Zen finally understands the concept of freedom and successfully rebels against The System and heads off into deep space.
Zen's visual interface was a large brown dome toward the front of the bridge with lights that flashed as it spoke; it was suggested in "Cygnus Alpha" that this 'visual reference point' was created by Zen to aid the crew after they asked it to show itself. Zen would simply make computer noises in place of speaking when overridden by The System.
Zen was capable of flying and fighting the Liberator on its own, with the notable exception of being unable to operate the teleport controls. It had banks of auxiliary computers that could be brought on-line when requested. These included navigation computers, which could pilot the Liberator to any known destination, and battle computers, that could formulate strategy, pilot the ship and operate the weapon systems during combat, even successfully fighting off a number of Federation pursuit ships without crew input ("Volcano"). Zen could also force the auto-repair systems to prioritize certain systems.
Zen had a chamber underneath its main dome that could perform instantaneous analysis of substances, such as the virus in "Project Avalon" or the drug in "Shadow". It also had access to more sophisticated analysis equipment, as demonstrated in its frantic attempts to find a solution to the corrosive space particles in "Terminal". Zen also had some crude telepathic ability. It operated a defense system against intruders that would use images of loved ones to draw them to their deaths. It could also form a temporary telepathic link with new crew - taking the name "Liberator" from Jenna's mind, for example.
Although open to instruction, Zen projected a dour, non-committal personality all of its own. In some of the early episodes, Zen would reply to certain questions with the phrase "That information is not available" and it was left open as to whether Zen was secretly executing its own agenda or genuinely couldn't help. In the episodes "Time Squad" and "Breakdown", Zen refused to help the crew carry out actions it believed endangered the ship, and even though it could not control the Teleport, it disabled the system by causing a circuit burnout. Zen did not display these characteristics from season two, possibly due to being re-programmed by Orac in the episode "Redemption".
Zen's massive database was a paradox within itself. The Federation was totally unaware of Liberator's origins (The System), yet Zen was able to provide information on Federation Planets, colonies, space ship designs and history, but it was unable (or unwilling) to recognise the two Drones from The System (Redemption) despite their architecture being of its own kind.
After the crew were forced to abandon the Liberator temporarily due to being badly damaged in the Intergalactic War, Zen was ordered to take commands only from the voice prints of certain members of the crew. The psychic defence barrier seen in Space Fall, was deactivated when Avon commanded Zen to allow an unrecognised ship to dock, which most likely contained Klegg and his troops. When Tarrant and Dayna joined the crew, their voice prints were added. Servalan's voice print was also added when she managed to take over the Liberator temporarily (The Harvest of Kairos), but it was removed when the crew re-took control.
It is likely that any other Deep Space Vehicles constructed by The System had Zen-like computers of their own.
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