I’m no expert in video game production, but I do know that your favourite video game was years in the making and that one of the starting points is the story. The story of Assassin’s Creed Black Flag is the basic MacGuffin plot where various parties attempt to secure an object (or as Star-Lord, you know, the legendary outlaw, might put it, - something having a “shiny suitcase, Ark of the Covenant, Maltese Falcon vibe”).
In Black Flag, the MacGuffin in question is the Observatory, a structure built by the precursor race to observe people. This is done with a device that is basically a high-tech version of the animus that uses a crystal cube – a prism if you will – containing the blood (DNA) of the person whose eyes you want to see through. Using such a device and having ample blood samples would allow a person to spy on anyone in the world.
Black Flag was released to the general public on 29 October 2013. This is important because four months earlier in June 2013 The Guardian newspaper in the United Kingdom published the initial revelations of NSA whistle-blower Edward Snowden. The article revealed the existence of a data mining program called PRISM which enables government agencies to spy on people through their online activities.