Sure, Batman: Arkham Asylum was awesome, but we could have gotten a very, very different product: It could have been a "rhythm action game" instead.
Speaking with GameInformer, members of the Rocksteady Studios team that developed the critically-acclaimed Batman: Arkham Asylum revealed some hidden details about the work that had gone into the game.
For instance: Did you know that some of the motion capture for Harley Quinn was done using one of the (male) producers? Or that three cans of whipped cream were used to create the sound effects for the explosive gel? Over the course of the development of Arkham Asylum - a game in which the word "Joker" is said 384 times - the team (consisting of 14 different nationalities) said hello to six newborn babies.
The most interesting little tidbit of information, though, is that we might have gotten a completely different game:
Combat went through three distinct revisions - the first one being a full rhythm action game! The second one was prototyped in 2D, which popped up whenever you got into a fight, and involved colored circles bashing into each other. This actually formed the basis of the final system.
...really? A rhythm action game? And a combat system with colored circles bashing into each other in 2D? Huh. I'm going to stick with the "fluid ballet of face-kicking" that made it into the final product, thank you very much.