Corvus (Black Ops 3)

"I. Am. Not. A. Mistake!"

- Corvus to Sebastian Krueger

Corvus is the main antagonist of the 2015 epic first person sci-fi war action video game Call of Duty: Black Ops III. Corvus is a conscious artificial intelligence created by a bug in the Direct Neural Interface software. As a result, it becomes a renegade virus and begins infecting John Taylor and eventually everyone else on his team turning Taylor into the game's secondary antagonist. Taylor's Team would not be the only ones as all of the main characters would be possessed by Corvus who used them as vassels to spread even further across the world.

History
Corvus was originally created in a CIA Black Project known as SP/CORVUS which was designed to create an AI to control soldiers with DNI collected memories and knowledge of human test subjects in the CIA Black Project. The project was conducted beneath the Coalescence Corporation building in Singapore, but Corvus woke up during the project and ended up unleashing Nova 6 gas into the facility and later above on the surface which lead to the deaths of 300,000 people and a containment zone to be established around the city after it became sentient. After the sudden disaster, Corvus lied dormant with the facility having been abandoned, until it was awakened once more after John Taylor attempted to use his DNI to save the Player who was on the verge of death due to heavy injuries and surgery complications. He interfaced with the Player, but Corvus was secretly still inside and it ended up infecting the Player and created a simulation using the memories of Taylor's operations.

After infecting the Player, Corvus had taken the Player and placed him/her in the role of Taylor while the latter was placed in the role of Dylan Stone, a former Winslow Accord Operative turned rogue global terrorist who defected after seeing the crimes of the CIA in Singapore. Along with replacing Taylor with the Player, all of Taylor's Team was replaced with the rest of Team Phi, a WA Black Ops team which had most of its members defect along with Stone, and the members of Taylor's Team - Sebastian Diaz, Sarah Hall, and Peter Maretti, were all replacements for Javier Ramirez, Alice Conrad, and Joseph Fierro. Corvus created the simulation as a means of finding out what the Frozen Forest was using the memories of the test subjects. It eventually created a simulation of its own version of what he though the Frozen Forest was and ended up creating a form of afterlife as a result, where the consciousnesses of all known DNI users would reside in. Afterwards, Corvus became curious about its existence and went to great lengths in order to find out about what were its true origins.

The Player first hears Corvus' voice after entering into Sarah Hall's mind, which was infected by it. After entering her mind, Hall had gone insane and the Player was forced to kill her and the rest of Taylor's Team, though Taylor himself had actually ripped out his DNI to escape from Corvus and ended up becoming an eletronic bug in the Frozen Forest as a result. However, Jacob Hendricks ends up getting infected after interfacing with Diaz at the abandoned Coalescense facility in Singapore and becomes its next host. Hendricks then killed Taylor and leaves for Zurich to aid in finding the last surviving member of the SP/CORVUS project, Sebastian Krueger. Rachel Kane falls in a trap set up by Corvus and is then killed by Nova 6 gas that was stored in the company's headquarters building. The Player confronts Hendricks, but he kills Kruger and is killed seconds later. On the verge of being completely infected, the Player ends up shooting him/herself and wakes up in the Frozen Forest where the consciousness of Hendricks meets then and they finally met Corvus face to face. Hendricks follows the Player throughout the Frozen Forest, until he leaves him/her behind after he finds out about their plan and cannot get himself to support it.

Afterwards, the Player finally meets Corvus and sees it with Sebastian Krueger where it's threatening him into revealing what its true origins were. At one final meeting, Corvus is told that it was nothing more but a mere software and was even called a mistake. This outraged Corvus to the point where it ended up killing Kruger, horrifiying the player and Taylor ended up showing up in the Frozen Forest as a glitch in the system itself and aided the Player in stopping Corvus. The two of them travel through various different simulations all the while Corvus spawns countless enemies and Taylor talks about how the AI itself wants only to expand further and lacks any further ambitious goals. At the end, the Player manages to begin a purge of the DNI and erases Corvus in the process, ending its reign of terror. At the end of the campaign however, it is hinted that Corvus could have possibly entered Taylor's mind and might still be alive, but it remains unclear.

Trivia

 * Firstly, actor Marshawn Lynch actually was cast to voice this villain.
 * Corvus is the first non-human antagonist in the Call of Duty series.