No, Batman: Arkham Knight won’t be requiring you to play on certain dates to unlock any Trophies like Arkham City did, but there is one date-related special event that only happens on Halloween. Keep in mind that the video above and the information below does contain spoilers.
The event can only be accessed if Man-Bat has been captured (the Creature of the Night mission needs to have been completed), and, of course, if the console or PC clock is set to October 31. Essentially, Man-Bat escapes his little holding cell, and Batman has to go around the city trying to get him back. The above video highlights exactly what happens in the short event.
Have you found any other date-related events or missions in Batman: Arkham Knight? If so, be sure to let us know about them in the comments below.