10 Open World Video Game Secrets You Never Found

The Batman Arkham series has provided us with several of the best superhero games ever created. From the excellent, atmospheric Asylum to the sprawling, open world Arkham City.

There are many nods to some of our favorite DC comic characters throughout the games, along with the assortment of Riddler trophies that we spent hours trying to collect. But one secret is so elaborate that many of us would have never encountered it.

Calendar Man is located in a holding cell inside the basement of the Solomon Wayne courthouse. On the wall in the room, a calendar is present with various dates circled. If you come back to the peculiar villain on each of these dates, he will deliver a unique monologue about an incident he caused in the past.

Most people will likely not return 12 times throughout a given year, so changing the time and date settings on your system will allow you to experience all of his stories and unlock the associated achievement.

This is obscure enough but there is actually a secret date that went undiscovered for some time. If you set your date to the day the development studio Rocksteady was founded, December 13th 2004, the Calendar Man will deliver a unique speech, warning that the 'end of days is coming' foreshadowing some of the events of the next entry in the series.