FATE
FATE is a supercomputer which was created by Belthasar made from Robo in the distant future. Based on the old Mother Brain circuit boards, FATE is self-aware and can operate alone. Referred to as the Goddess of Fate by the people of El Nido, FATE operates as an unseen villain until late in the game.
Following the Time Crash, FATE would not risk discovery of Chronopolis or the Flame by populations of the past, which could compromise her creation in the future. It took every measure to prevent this, sealing off the Sea of Eden. FATE created the islands comprising El Nido through terraforming. They were populated by the Chronopolis scientists and their descendants, brainwashed to be able to live a peaceful life in FATE's 'paradise'. FATE began distributing 'Records of Fate' (green diamond-shaped devices) across El Nido, which the denizens consulted daily. Unbeknownst to the human subjects, FATE used the Records to subconsciously control the minds of the El Nido population, subtly manipulating each person's individual judgement to stop them from leaving El Nido and interfering with history. Using machines to run Chronopolis, FATE was able to monitor El Nido with efficiency and halt any tampering.
When the young Serge came into contact with the Frozen Flame, the Prometheus Circuit, a stand-alone program, sealed it away so not even FATE could access it. Unable to draw power from the Flame, FATE's control over El Nido was effectively severed. It single-mindedly set itself to remove all obstacles. During the events of the game, Lynx schemed to be able to possess Serge's body, since that would allow him to enter the Flame's door (which recognizes only the body of its "arbiter"). Lynx succeeded and indeed managed to release the Flame's lock. It is revealed that FATE's desire was to use the Flame to reincarnate itself into a real, and new, living species. Lynx/FATE was defeated by the real Serge, however, before she could realize her dream.
In Chrono Trigger, FATE's original form was of the holographic artificially intelligent Mother Brain, which governed the future's robot population. Because the Day of Lavos will no longer occur (following the first game), this event is erased from existence.