Batman: Arkham Knight - 15 Hidden Easter Eggs, References & Secrets You Need To Find

3. John 'Martian Manhunter' Jones Has Been Through Gotham

The GCPD Precinct really is a great place to explore if you have the time or inclination, as being this is the first game to fully explore Gotham - and not just a wing of it designated as 'Arkham City' - you have to imagine a huge number of characters from the greater DC universe have passed through. One such legendary hero is John Jones, the fictional identity adopted by one of DC's oldest characters, Martian Manhunter. As a detective and one of the original members of the Justice League he fits into Batman's world perfectly, as well as again hinting at a wider Justice League/Superman-focussed future for the developers.