Spoiler: While not tied to the plot, this story and the accompanying video does contain information about Ubisoft's upcoming pirate game. Be warned.
There's been some speculation about what, if any, connection Ubisoft's upcoming hacker-centric Watch Dogs has with Assassin's Creed. Watch Dogs depicts a hacker vigilante fighting the power of a corrupt city and the company that controls it. Assassin's Creed also includes hackers fighting one front of a war against a corrupt, controlling corporation.
Assassin's Creed 4 game director Ashraf Ismail teased a connection between the series and Ubisoft's recently delayed Watch Dogs at this year's E3 conference in an on-camera interview with Elder Geek. After playing through Assassin's Creed 4 for Polygon's review, I can confirm that connection — though what it means for either series is up for debate.
Ubisoft's new franchise crosses over with its heaviest hitter in a seemingly innocuous way: While hacking computers in the Abstergo offices, you can find a brochure for the Blume Corporation, the company responsible for Watch Dog's ctOS security system and protocol, along with comments from Abstergo personnel about Blume and ctOS.
It's unclear whether this is a sign of an official connection between Watch Dogs and the Assassin's Creed series that could be explored in future games, or if the brochure is just an Easter Egg.
Check out Polygon's full Assassin's Creed 4 review here.