Likewise, Tom Kane, Kimberly Brooks, Wally Wingert, Tasia Valenza, Fred Tatasciore, Danny Jacobs, Steve Blum, and James Horan reprise their respective roles from the first game as Quincy Sharp, Oracle, the Riddler, Poison Ivy, Bane, Zsasz, Killer Croc, and Jack Ryder. Though Tom doesn't reprise the role of Commissioner Gordon and Fred gets double duty as Solomon Grundy and Mr. Hammer.
Grey DeLisle is Catwoman. note Like Tara Strong, she did voices in the DCAU incarnation of Batman (she, along with the returning Tasia Valenza voiced the two servant girls sent to look after Max in the second part of "Curse of the Kobra" on Batman Beyond), The Batman (most notably, Robin's mother and a Gender Flipped version of Vulture of the Terrible Trio), and Batman The Brave And The Bold (Black Canary).
Steve Blum lends his talent, of course, aside from Croc's cameo. Notably, using his Wolverine voice for one of the thugs that Catwoman fights at in the beginning of the game. He's also Mr. Sickle.
The Other Darrin: Tara Strong replaces Arleen Sorkin as Harley Quinn and David Kaye replaces Tom Kane as Commissioner Gordon. Perplexing since, as noted above, Tom reprised another role from the first game, Quincy Sharp.
In an interview, director Sefton Hill said they wanted to include a reference to the infamous Bat-Shark Repellent Spray from the Adam West seriesnote Reportedly, when confronted by "Tiny" in the Iceberg Lounge, Batman would break out the repellent... then open it up to reveal a set of brass knuckles, but ended up nixing it because they felt it was a Level Breaker. There's still a subtle reference; if you get killed by the shark, one of the possible hints reminds you to remember Batman's shark repellent: a flurry of blows to drive it off.
In one room, you can listen to the Riddler mutter about ways to take down Batman, and ponders taking Penguin's shark, only to say that there are "too many variables", and that Batman likely has some sort of "shark contingency".
The plot itself borrows ideas from Knightfall and No Man's Land, among other famous Batman stories. A lot of the Joker/Batman dynamic is reminiscent of The Killing Joke.