- Fake Australian: The English-American Greg Ellis plays Captain Boomerang.
- Fake Russian: The American Nolan North plays KGBeast.
- The Other Darrin:
- Despite reprising the role from The Batman, Hynden Walch is this to the Arkham-verse Harley Quinn, replacing Arleen Sorkin (Harley's original voice in both Batman: The Animated Series and Batman: Arkham Asylum) and Tara Strong (Harley's voice in Arkham City, Arkham Origins, and Arkham Knight).
- Neal McDonough replaces Chris Cox from the Batman: Arkham Series proper as Deadshot. This despite Cox appearing as Commissioner Gordon.
- Speaking of Cox as Gordon, he's the fourth voice actor for the Arkham-verse version of Jim Gordon, replacing Tom Kane (Asylum), David Kaye (City), and Michael Gough (Origins and Blackgate).
- Matthew Gray Gubler replaces Wally Wingert as the Riddler.
- Despite reprising the role from the Batman: The Brave and the Bold episode "Chill of the Night!", Jennifer Hale is this to the Arkham-verse Poison Ivy, replacing Tasia Valenza (Asylum and City) and Amy Carle (Lockdown).
- John DiMaggio replaced Fred Tatasciore (Asylum and City) and JB Blanc (Origins) as Bane.
- Christian Lanz replaced Dino Andrade (Asylum) as the Scarecrow and Danny Jacobs as Zsasz.
- Playing Against Type: Hynden Walch playing Harley is even more against type here due to the movie being rated PG-13 as opposed to the TV-Y7 rating of The Batman, and thus would be crazier here.
- Role Reprise:
- As noted in the main page, Kevin Conroy as Batman, C.C.H. Pounder as Amanda Waller, Troy Baker as the Joker, Hynden Walch as Harley Quinn, and Jennifer Hale as Killer Frost. There's also Martin Jarvis as Alfred and Nolan North as the Penguin.
- In the French dub, only three of the voice actors from the Arkham games made before this movie was released reprised their roles here: Adrien Antoine as Batman/Bruce Waynenote , Philippe Peythieu as the Penguin note , and Jean-Claude Sachot as Commissioner Gordonnote . Other role reprises include Kelvine Dumour as Harley Quinnnote , Xavier Fagnon as the Jokernote , Alexandre Gillet as the Riddlernote , and Pierre Dourlens as Alfrednote .
Trivia / Batman: Assault on Arkham