A final Fixer contract in Watch_Dogs asks you to kill a certain target, named Oliver. If you have played Assassin's Creed IV: Black Flag, you may have made the acquaintance of a man named Oliver Garneau. He eventually leaves for Chicago, to attend a meeting with shareholders. While he is there, he falls out of contact and no one at Abstergo knows why. Thus, his appearance in Watch_Dogs is an Easter egg that explains the man's disappearance in the other game.