4 books in series

Batman: The Arkham Saga

Batman: The Arkham Saga is a 4-book series with 4 primary works first released in 2013 with contributions by Derek Fridolfs, Paul Dini, Peter J. Tomasi, and Alexander C. Irvine.

Batman: Arkham Unhinged, Vol. 1
Batman: Arkham Knight, Vol. 1
Batman: Arkham Knight, Vol. 2
Batman: Arkham Knight - The Riddler's Gambit