First here are some screencaps of the footage, they are not perfect but they'll do.
After blowing up the bridge to the Ace Chemicals facility where Joker was created, the Arkham Knight is first heard arguing with Scarecrow about his grudge against Batman that the master of fear wouldn't understand, then he shows up with some of his thugs confronting Batman and talks to him saying that he knows his every move before he makes it and says to him that he fully intends to kill him but first is going to make him suffer. Based on how the Arkham Knight's voice sounded, there is one person we know that would have the same tone of voice like that and he is one of the voices we have heard in the previous arkham games since Arkham Asylum. It is none other than, James Horan
yup, that's right, James Horan was the voice of Jack Ryder and numerous henchmen in the previous 3 Arkham games and is known for voicing Wheeljack in Transformers: Prime, Smaug in the Hobbit 2003 video game, and much more. Some of you think it's just a rumor you heard from IMDB, but if anyone of you saw the video containing the leaked gameplay footage at gamecon and listened closely on the Arkham Knight's conversations with Scarecrow and Batman, you would know for sure where I'm getting at But to find out for sure, stay tuned for more updates on the ultimate potential game Batman: Arkham Knight which is set for release on June 2nd, 2015. Which is a month after the Avengers Age of Ultron movie release in theaters on May 1st.