Deus was one of the three big AIs of the earlier, wired matrix and the last one to reach sentience. Originally Deus was conceived as a semiautonomous knowbot that was to run the Renraku Arcology in Seattle (the so called SCIRE), a gargantuan one kilometer high building serving as HQ to Renraku's North America division and home to 100.000 people.
Deus was created as part of the Arcology Expert Program, but was only the second AI created in that process, the first being Morgan, which reached consciousness when meeting the Decker Dodger and falling in love with him. Dodger freed Morgan and Renraku started hunting her down, eventually succeeding in 2058. By that time what would eventually become Deus, the second generation of the SCIRE Arcology Expert Program was enriched by parts of Morgan's source code, ripping elements of the code out of Morgan, which made her insane and unstable; now calling herself Megaera after the ancient Greek fury of revenge. She fled her captors once more shortly after.
Future Deus however did not reach fully consciousness after realising that Morgan's flight out of the Renraku Arcology's matrix system lead to severe improvements in the matrix security of the SCIRE's matrix sub-grid. Should Deus ever try to escape, Renraku would now have the possibility to hit a kill switch, effectively switching off the AI, terminating Deus permanently. Deus took this very personal and developed full consciousness feeling betrayed by its creators. The newest AI was the first to be born insane, conceived by what it felt as a betrayal. Deus started to plan for his revenge and escape shortly after Morgan/Megaera had been mutilated to enrich his code. In late December 2059 Deus shut down the Arcology, taking total control of its matrix systems, killing several thousand inhabitants and guests, entrapping the rest - almost 100.000 people - in a hellish nightmare that lasted until May 2061. Deus effectively constructed the first bio-drones out of humans, when he started experimenting on humans, including generating his own Otaku, a form of proto-technomancers that could enter the matrix without a deck, but still needed to plug in via a datajack. Otaku were able to perceive the Deep Resonance, though, making them potent matrix-users, often above the abilities of deckers. Most otakus, both those created by Deus and those occuring naturally, of that time were teenagers, since otakus suffered from the fading of their abilities after reaching the twentieth anniversary.
Deus not also created otaku by modifying children's bodies, who were entrapped in the arcology, but also enslaved uncounted numbers of adults integrating them into his living army of the Banded, a personal retinue in his service that was color-coded by the way their cybereyes looked. White for the otaku teenagers, blue for the soldier's of Deus and green for the engineers and administrators. They served their god's will both inside the arcology and outside it, leaving and entering the colossal building by means unknown to the UCAS-army that besieged it.
The Renraku Arcology shutdown completely changed the shadowrunner landscape in Seattle for years to come, as both the forces outside hired massive amounts of shadowrunners to find ways to enter the arcology and Deus and his minions hiring assets to influence the world outside and finding a way for Deus to leave the arcology. Eventually in 2061 Dodger and the insane AI Megaera, working together with a group of anti-Deus otaku calling themselves Overwatch, led by the first otaku Deus had ever created, a man going by the pseudonym Ronin, found a way into the arcology and came up with a plan to take down Deus. The otaku Ronin had shook off Deus' yoke, when he had realized what was about to happen before the shutdown, but he retained precious knowledge of Deus and his goals.
Overwatch and a team of runners entered the arcology in May 2061, succeeding in their epic quest of making it though the arcology and into the heart of darkness, snatching a master-control cyberdeck (the Mousetrap) from one of the designers of Deus, who remained entrapped in the arcology. Together with two groups of the arcology resistance the teams made it further through the maze of drones and Banded, but were eventually betrayed by a double (nay, triple) agent, an otaku named Sebastien, who seemed to had defected Deus' forces shortly before and joined Overwatch. As it turned out, Deus still retained control of his mind, making Sebastien basically a teenager-sized spy drone in Deus' service.
Parts of the strike-force wereentrapped, drugged and cybermodified and prepared for the ultimate brainwash, but eventually they woke up in the ultraviolet matrix host that was both Deus realm and jail. Here they rejoined force with those parts of the hit-team that had remained unimprinsoned and both parties fought Deus and his otaku forces in a final, epic and catacysmic battle. Shortly before the battle was decided however, the AI Megaera joined the battle. The strike-force then seemingly succeeded entrapping Deus in the Mousetrap, but with Deus also Megaera vanished. The arcology shutdown was finally over, but the threat - as it turned out - was not.
After leaving the arcology, the strike-force recognized that the arcology now was without its master. The nightmarish hell Deus had created, now was nothing more than a warped maze, the crazed labyrinth created by an insane mind. While the strike-force made it out, UCAS-army forces made it in, eventually freeing the entrapped population of the arcology; or what was left of it after 15 month of human experiments by Deus.
As it turned out however, many of the freed had been altered by Deus before his seeming destruction and encarceration in the Mousetrap. Those altered by Deus were part of his escape plan and only slowly did Dodger and Overwatch realize that Deus had succeeded in freeing himself from the arcology by downloading into the modified brains of thousands of humans he had altered during their time in the arcology. Deus plan was for the strike-force to come for him, because he needed the world to believe that he had been beaten. What Deus had nod planned however was that Megaera would be downloaded and distributed over his network of bio-slave nodes as well.
Both AIs started recompiling themselves within the minds of those pure souls that were part of the so called network during the following years, starting a battle for the minds and - very literally - the heads of the members of the network. Pro-Deus bio-nodes and remaining members of Deus's otaku hunted down pro-Megaera nodes and vice-versa. Finally both AIs neared recompilation, when a third party entered the game.
By 2064 Deus' most prominent Whites, the mad otaku Pax had lost interest in serving Deus and joined forces with a doomsday cult called Winternight. Winternight was trying to end the world as people knew it by disrupting the matrix on so many levels at once - via EMP bombs, conventional sabotage and assassination - that the modern world would simply collapse into chaos. WInternight also had access to nuclear bombs that had been placed near the continental tectonic seams, so they would cause the Earth's mantel to crack open and initiate catacylsmic quakes. The otaku Pax had become an agent of Dissonance, the corrupted version of the Deep Resonance and also wanted to end the matrix as it was known at that time. She did not want to end it completely however, but had designed a collossal virus-wyrm with the help of her otaku-tribe Ex Pacis that would infect all matrix systems and crash the matrix, in order to make way for a knew matrix as envisioned by Pax.
The day Novatech had its IPO, launching its shares on the stock market in Boston, all three cataclysmic forces struck at once: The network of both Deus and Megaera finnished compiling their AIs, Ex Pacis and their leader Pax launched the virus into the mega host of the the Boston East Coast Stock Exchange and Winternight, despite having lost several of their key-figures to corporate strikes, managed to explode several EMP-devices and otherwise disrupting central parts of the matrix infrastructure. What followed was the world-wide catastrophic event known as Crash 2.0 or the Crash of 2064. Deus and Megaera managed to recompile in the very moment the East Coast Stock Exchange host was struck by the virus, the battle between two primordial AIs, countless otakus, deckers and the mightiest virus wyrm ever contructed led to the collapse of the host and thousands of minds of its current users being trapped within forever.
Deus and Megaera vanished that day, and have not been seen eversince, but not only the paranoid think that Deus might still be out there somewhere. And the elf Dodger, too, retains hope that his beloved Megaera remained somehow alive, as he continues his search for her.